JAVA System.out.println equation - java

Can someone explain to me why the following code prints the char 'u' ?
int p = 9;
int q = 5;
int r = p - q;
double x = p;
double y = q;
String s = "Question";
System.out.println ((char)(s.charAt(r) + 1));

1) p-q = 4
2) character at index 4 is t (s.chartAt(4) gives character at index 4 in string s).
3) you have added 1 to it so 1 was added to its ASCII value making the ASCII value equal to ASCII value of u.
4) then the integer was cast to char which will be 'u', which was printed.

Because s.charAt(r) = 't' and 't' as int is 116. 116 + 1 is 117 and 117 as char is u;
If you split up the oneliner it might be more clear:
char charAtR = s.charAt(r);
int plusOne = charAtR + 1; // char will be converted to int
char toPrint = (char) plusOne;
System.out.println (toPrint);

In System.out.println() you receive character 't' from string "Question" and output next codePoint that is 'u'.

You take char at position 4 (since r is p - q, which is 4) in string s, and its t. In s.charAt('t') you take its char value (ASCII code), which is 116, and you add 1 to it, so you will 117, which is ASCII code of u and you turn it in char, so it will print u.
For example, if you do this:
String s = "Question";
System.out.println((int)s.charAt(r));
It will print 116. If you do this:
String s = "Question";
System.out.println((char) 177);
It prints u.
If you're wondering why is t at position 4, and not s, thats because charAt works from 0, not from 1.

The value of r is 4. Therefore,
s.charAt(r); = s.charAt(4); = ELEMENT AT 4th INDEX OF "Question" = 't'
When an integer is added to a char (eg. 'A'+1) or the post increment operator is used with a char (eg. char_variable++), the ASCII value of the char is incremented.
So,
s.charAt(r)+1 = (char)((ASCII value of 't')+1) = (char)(116+1) = 'u'
Since 117 is the ASCII value of 'u', the program displays 'u'.

Related

The conversion of int to char is not printing anything [duplicate]

Below is a code snippet,
int a = 1;
char b = (char) a;
System.out.println(b);
But what I get is empty output.
int a = '1';
char b = (char) a;
System.out.println(b);
I will get 1 as my output.
Can somebody explain this? And if I want to convert an int to a char as in the first snippet, what should I do?
int a = 1;
char b = (char) a;
System.out.println(b);
will print out the char with Unicode code point 1 (start-of-heading char, which isn't printable; see this table: C0 Controls and Basic Latin, same as ASCII)
int a = '1';
char b = (char) a;
System.out.println(b);
will print out the char with Unicode code point 49 (one corresponding to '1')
If you want to convert a digit (0-9), you can add 48 to it and cast, or something like Character.forDigit(a, 10);.
If you want to convert an int seen as a Unicode code point, you can use Character.toChars(48) for example.
My answer is similar to jh314's answer but I'll explain a little deeper.
What you should do in this case is:
int a = 1;
char b = (char)(a + '0');
System.out.println(b);
Here, we used '0' because chars are actually represented by ASCII values. '0' is a char and represented by the value of 48.
We typed (a + '0') and in order to add these up, Java converted '0' to its ASCII value which is 48 and a is 1 so the sum is 49. Then what we did is:
(char)(49)
We casted int to char. ASCII equivalent of 49 is '1'. You can convert any digit to char this way and is smarter and better way than using .toString() method and then subtracting the digit by .charAt() method.
It seems like you are looking for the Character.forDigit method:
final int RADIX = 10;
int i = 4;
char ch = Character.forDigit(i, RADIX);
System.out.println(ch); // Prints '4'
There is also a method that can convert from a char back to an int:
int i2 = Character.digit(ch, RADIX);
System.out.println(i2); // Prints '4'
Note that by changing the RADIX you can also support hexadecimal (radix 16) and any radix up to 36 (or Character.MAX_RADIX as it is also known as).
int a = 1;
char b = (char) a;
System.out.println(b);
hola, well i went through the same problem but what i did was the following code.
int a = 1
char b = Integer.toString(a).charAt(0);
System.out.println(b);
With this you get the decimal value as a char type. I used charAt() with index 0 because the only value into that String is 'a' and as you know, the position of 'a' into that String start at 0.
Sorry if my english isn't well explained, hope it helps you.
you may want it to be printed as '1' or as 'a'.
In case you want '1' as input then :
int a = 1;
char b = (char)(a + '0');
System.out.println(b);
In case you want 'a' as input then :
int a = 1;
char b = (char)(a-1 + 'a');
System.out.println(b);
java turns the ascii value to char :)
int a = 1;
char b = (char) (a + 48);
In ASCII, every char have their own number. And char '0' is 48 for decimal, '1' is 49, and so on. So if
char b = '2';
int a = b = 50;
Nobody has answered the real "question" here: you ARE converting int to char correctly; in the ASCII table a decimal value of 01 is "start of heading", a non-printing character. Try looking up an ASCII table and converting an int value between 33 and 7E; that will give you characters to look at.
Whenever you type cast integer to char it will return the ascii value of that int (once go through the ascii table for better understanding)
int a=68;
char b=(char)a;
System.out.println(b);//it will return ascii value of 68
//output- D
If we are talking about class types - not primitives, the following trick has to be done:
Integer someInt;
Character someChar;
someChar = (char)Integer.parseInt(String.valueOf(someInt));
First, convert the int (or another type) to String,
int a = 1;
String value = String.valueOf(a);
Then, convert that String to char.
char newValue = value.charAt(0);
You can avoid empty output in this way...
System.out.println(newValue);
In java a char is an int. Your first snippet prints out the character corresponding to the value of 1 in the default character encoding scheme (which is probably Unicode). The Unicode character U+0001 is a non-printing character, which is why you don't see any output.
If you want to print out the character '1', you can look up the value of '1' in the encoding scheme you are using. In Unicode this is 49 (the same as ASCII). But this will only work for digits 0-9.
You might be better off using a String rather than a char, and using Java's built-in toString() method:
int a = 1;
String b = toString(a);
System.out.println(b);
This will work whatever your system encoding is, and will work for multi-digit numbers.
if you want to print ascii characters based on their ascii code and do not want to go beyond that (like unicode characters), you can define your variable as a byte, and then use the (char) convert. i.e.:
public static void main(String[] args) {
byte b = 65;
for (byte i=b; i<=b+25; i++) {
System.out.print((char)i + ", ");
}
BTW, the ascii code for the letter 'A' is 65
Make sure the integer value is ASCII value of an alphabet/character.
If not then make it.
for e.g. if int i=1
then add 64 to it so that it becomes 65 = ASCII value of 'A'
Then use
char x = (char)i;
print x
// 'A' will be printed
There is one method by which int can be converted to char and even without using ASCII values.
Example:
int i = 2;
char ch = Integer.toString(i).charAt(0);
System.out.println(ch);
Explanation :
First the integer is converted to string and then by using String function charAt(), character is extracted from the string. As the integer only has one single digit, the index 0 is given to charAt() function.
My solution is for converting lower case alphabets (a-z) to (0-25) and vice versa.
My answer is for a specific use-case it is not generic solution my solution will help you if you want to store the frequency of character into an integer array of size 26 instead of using Hashmap<Character,Integer>
----> for converting 0 to 25 into a-z
char ch=(char)(0+'a'); // output 'a' // input 0(as integer)
char ch=(char)(25+'a'); // output 'z' // input 25(as integer)
---->for converting a to z into 0-25
int freq='a'-'a' // output 0 // input 'a'
int freq='b'-'a' // output 1 // input 'b'
int freq='c'-'a' // output 2 // input 'c'
int freq='z'-'a' // output 25 // input 'z'
Again this approach will help you to get the frequency of characters as well as characters
public class Main
{
public static void main(String[] args) {
String s="rajatfddfdf";
int freq[]= new int[26];
for(int i=0;i<s.length();i++){
char characterAtIndex=s.charAt(i);
freq[characterAtIndex-'a']+=1;
}
for(int i=0;i<26;i++){
System.out.println((char)('a'+i)+" frequency="+freq[i]);
}
}
}
by using the above code we can get the frequency as well as character using integer array of size 26 . We can write if-else logic if you don't want to include the character with frequency 0.
look at the following program for complete conversion concept
class typetest{
public static void main(String args[]){
byte a=1,b=2;
char c=1,d='b';
short e=3,f=4;
int g=5,h=6;
float i;
double k=10.34,l=12.45;
System.out.println("value of char variable c="+c);
// if we assign an integer value in char cariable it's possible as above
// but it's not possible to assign int value from an int variable in char variable
// (d=g assignment gives error as incompatible type conversion)
g=b;
System.out.println("char to int conversion is possible");
k=g;
System.out.println("int to double conversion is possible");
i=h;
System.out.println("int to float is possible and value of i = "+i);
l=i;
System.out.println("float to double is possible");
}
}
hope ,it will help at least something
If you want to convert a character to its corresponding integer, you can do something like this:
int a = (int) 'a';
char b = (char) a;
System.out.println(b);
This happens because in ASCII there are some items that can not be printed normally.
For example, numbers 97 to 122 are integers corresponding to the lowercase letters a to z.
public class String_Store_In_Array
{
public static void main(String[] args)
{
System.out.println(" Q.37 Can you store string in array of integers. Try it.");
String str="I am Akash";
int arr[]=new int[str.length()];
char chArr[]=str.toCharArray();
char ch;
for(int i=0;i<str.length();i++)
{
arr[i]=chArr[i];
}
System.out.println("\nI have stored it in array by using ASCII value");
for(int i=0;i<arr.length;i++)
{
System.out.print(" "+arr[i]);
}
System.out.println("\nI have stored it in array by using ASCII value to original content");
for(int i=0;i<arr.length;i++)
{
ch=(char)arr[i];
System.out.print(" "+ch);
}
}
}

Why does this equation return the answer it does?

I am Confused as to why this returns 1;
(char)('0' + 11) = ; why?
Full code below where ending = 1;
char[] ending;
char a = (char)('0' + 11/10);
ending = new char[]{a, (char)('0' + 11)};
System.out.println(ending);
Char value of '0' is 48.
48 + 11 = 59
Char value of 59 is ';'.
You can check char values in integer value in any ASCII Character Set in internet.
In Java, char can be use as a int, short, byte, long with values between 0 and 65535 without any casting.
A better explanation is found in: Java char is also an int?
You are assigning '1' to variable a. '0' + 11/10 => '0' + 1
You are assigning a two letter string to endings. Le first letter is a ('1') the second is a semi colon. ('0' + 11).

Converting int to char in same integer format [duplicate]

Below is a code snippet,
int a = 1;
char b = (char) a;
System.out.println(b);
But what I get is empty output.
int a = '1';
char b = (char) a;
System.out.println(b);
I will get 1 as my output.
Can somebody explain this? And if I want to convert an int to a char as in the first snippet, what should I do?
int a = 1;
char b = (char) a;
System.out.println(b);
will print out the char with Unicode code point 1 (start-of-heading char, which isn't printable; see this table: C0 Controls and Basic Latin, same as ASCII)
int a = '1';
char b = (char) a;
System.out.println(b);
will print out the char with Unicode code point 49 (one corresponding to '1')
If you want to convert a digit (0-9), you can add 48 to it and cast, or something like Character.forDigit(a, 10);.
If you want to convert an int seen as a Unicode code point, you can use Character.toChars(48) for example.
My answer is similar to jh314's answer but I'll explain a little deeper.
What you should do in this case is:
int a = 1;
char b = (char)(a + '0');
System.out.println(b);
Here, we used '0' because chars are actually represented by ASCII values. '0' is a char and represented by the value of 48.
We typed (a + '0') and in order to add these up, Java converted '0' to its ASCII value which is 48 and a is 1 so the sum is 49. Then what we did is:
(char)(49)
We casted int to char. ASCII equivalent of 49 is '1'. You can convert any digit to char this way and is smarter and better way than using .toString() method and then subtracting the digit by .charAt() method.
It seems like you are looking for the Character.forDigit method:
final int RADIX = 10;
int i = 4;
char ch = Character.forDigit(i, RADIX);
System.out.println(ch); // Prints '4'
There is also a method that can convert from a char back to an int:
int i2 = Character.digit(ch, RADIX);
System.out.println(i2); // Prints '4'
Note that by changing the RADIX you can also support hexadecimal (radix 16) and any radix up to 36 (or Character.MAX_RADIX as it is also known as).
int a = 1;
char b = (char) a;
System.out.println(b);
hola, well i went through the same problem but what i did was the following code.
int a = 1
char b = Integer.toString(a).charAt(0);
System.out.println(b);
With this you get the decimal value as a char type. I used charAt() with index 0 because the only value into that String is 'a' and as you know, the position of 'a' into that String start at 0.
Sorry if my english isn't well explained, hope it helps you.
you may want it to be printed as '1' or as 'a'.
In case you want '1' as input then :
int a = 1;
char b = (char)(a + '0');
System.out.println(b);
In case you want 'a' as input then :
int a = 1;
char b = (char)(a-1 + 'a');
System.out.println(b);
java turns the ascii value to char :)
int a = 1;
char b = (char) (a + 48);
In ASCII, every char have their own number. And char '0' is 48 for decimal, '1' is 49, and so on. So if
char b = '2';
int a = b = 50;
Nobody has answered the real "question" here: you ARE converting int to char correctly; in the ASCII table a decimal value of 01 is "start of heading", a non-printing character. Try looking up an ASCII table and converting an int value between 33 and 7E; that will give you characters to look at.
Whenever you type cast integer to char it will return the ascii value of that int (once go through the ascii table for better understanding)
int a=68;
char b=(char)a;
System.out.println(b);//it will return ascii value of 68
//output- D
If we are talking about class types - not primitives, the following trick has to be done:
Integer someInt;
Character someChar;
someChar = (char)Integer.parseInt(String.valueOf(someInt));
First, convert the int (or another type) to String,
int a = 1;
String value = String.valueOf(a);
Then, convert that String to char.
char newValue = value.charAt(0);
You can avoid empty output in this way...
System.out.println(newValue);
In java a char is an int. Your first snippet prints out the character corresponding to the value of 1 in the default character encoding scheme (which is probably Unicode). The Unicode character U+0001 is a non-printing character, which is why you don't see any output.
If you want to print out the character '1', you can look up the value of '1' in the encoding scheme you are using. In Unicode this is 49 (the same as ASCII). But this will only work for digits 0-9.
You might be better off using a String rather than a char, and using Java's built-in toString() method:
int a = 1;
String b = toString(a);
System.out.println(b);
This will work whatever your system encoding is, and will work for multi-digit numbers.
if you want to print ascii characters based on their ascii code and do not want to go beyond that (like unicode characters), you can define your variable as a byte, and then use the (char) convert. i.e.:
public static void main(String[] args) {
byte b = 65;
for (byte i=b; i<=b+25; i++) {
System.out.print((char)i + ", ");
}
BTW, the ascii code for the letter 'A' is 65
Make sure the integer value is ASCII value of an alphabet/character.
If not then make it.
for e.g. if int i=1
then add 64 to it so that it becomes 65 = ASCII value of 'A'
Then use
char x = (char)i;
print x
// 'A' will be printed
There is one method by which int can be converted to char and even without using ASCII values.
Example:
int i = 2;
char ch = Integer.toString(i).charAt(0);
System.out.println(ch);
Explanation :
First the integer is converted to string and then by using String function charAt(), character is extracted from the string. As the integer only has one single digit, the index 0 is given to charAt() function.
My solution is for converting lower case alphabets (a-z) to (0-25) and vice versa.
My answer is for a specific use-case it is not generic solution my solution will help you if you want to store the frequency of character into an integer array of size 26 instead of using Hashmap<Character,Integer>
----> for converting 0 to 25 into a-z
char ch=(char)(0+'a'); // output 'a' // input 0(as integer)
char ch=(char)(25+'a'); // output 'z' // input 25(as integer)
---->for converting a to z into 0-25
int freq='a'-'a' // output 0 // input 'a'
int freq='b'-'a' // output 1 // input 'b'
int freq='c'-'a' // output 2 // input 'c'
int freq='z'-'a' // output 25 // input 'z'
Again this approach will help you to get the frequency of characters as well as characters
public class Main
{
public static void main(String[] args) {
String s="rajatfddfdf";
int freq[]= new int[26];
for(int i=0;i<s.length();i++){
char characterAtIndex=s.charAt(i);
freq[characterAtIndex-'a']+=1;
}
for(int i=0;i<26;i++){
System.out.println((char)('a'+i)+" frequency="+freq[i]);
}
}
}
by using the above code we can get the frequency as well as character using integer array of size 26 . We can write if-else logic if you don't want to include the character with frequency 0.
look at the following program for complete conversion concept
class typetest{
public static void main(String args[]){
byte a=1,b=2;
char c=1,d='b';
short e=3,f=4;
int g=5,h=6;
float i;
double k=10.34,l=12.45;
System.out.println("value of char variable c="+c);
// if we assign an integer value in char cariable it's possible as above
// but it's not possible to assign int value from an int variable in char variable
// (d=g assignment gives error as incompatible type conversion)
g=b;
System.out.println("char to int conversion is possible");
k=g;
System.out.println("int to double conversion is possible");
i=h;
System.out.println("int to float is possible and value of i = "+i);
l=i;
System.out.println("float to double is possible");
}
}
hope ,it will help at least something
If you want to convert a character to its corresponding integer, you can do something like this:
int a = (int) 'a';
char b = (char) a;
System.out.println(b);
This happens because in ASCII there are some items that can not be printed normally.
For example, numbers 97 to 122 are integers corresponding to the lowercase letters a to z.
public class String_Store_In_Array
{
public static void main(String[] args)
{
System.out.println(" Q.37 Can you store string in array of integers. Try it.");
String str="I am Akash";
int arr[]=new int[str.length()];
char chArr[]=str.toCharArray();
char ch;
for(int i=0;i<str.length();i++)
{
arr[i]=chArr[i];
}
System.out.println("\nI have stored it in array by using ASCII value");
for(int i=0;i<arr.length;i++)
{
System.out.print(" "+arr[i]);
}
System.out.println("\nI have stored it in array by using ASCII value to original content");
for(int i=0;i<arr.length;i++)
{
ch=(char)arr[i];
System.out.print(" "+ch);
}
}
}

How can an int be declared with ' ' and why is '2' == 50?

Question is: What gets displayed in console?
And I really have some problems with understanding.
Here is the code:
public static void felda(){
char[] felda = {'2',0x31,48};
for (int i = 0; i< felda.length; i++){
System.out.println(" : " + felda[i]);
}
System.out.println();
}
public static void feldb(){
int[] feldb = {'2',0x31,48};
for (int i = 0; i< feldb.length; i++){
System.out.println(" : " + feldb[i]);
}
System.out.println();
}
public static void feldc(){
int [] feldc = {'2',0x31,48};
for (int i = 0; i< feldc.length; i++){
System.out.println(" : " + (char) feldc[i]);
}
System.out.println();
}
So if I run in the Solution is:
: 2
: 1
: 0
: 50
: 49
: 48
: 2
: 1
: 0
So I don't understand how it is even possible to have an int definded with ' '.
And I find it very confusing how int feldb = '2' results in being 50 and int feldb=0x31 results in being 49.. dam this is all so confusing. I hope someone can enlighten me.
Edit: Why is char feldc = 48; resulting in being 0?
In Java, a char represents a Unicode character. But it's also in fact an unsigned integer, on 2 bytes, which can go from 0 to 216 - 1.
So,
char c = '2';
initializes c with the character '2'. And the numeric value of the character '2', in Unicode, is 50.
So, if you print it as a character, '2' will be printed. If you print it as a numeric value (as an int, using int c = '2'), 50 will be printed.
When doing
char feldc = 48;
you initialize feldc with the character whose numeric Unicode value is 48, and that character is the character '0'. It's thus equivalent to
char feldc = '0';
0x31 is a number written as an hexadecimal literal (that's what the 0xprefix means). When you write 31, the value is in decimal. It's equal to 1 * 100 + 3 * 101.
In hexadecimal, the base is 16 rather than 10. So 0x31 is equal to 1 * 160 + 3 * 161, which is equal to 49.
50 is the ASCII value of the '2' character. Defined like that its not the number 2.. its giving the ASCII value of a character. See this ASCII table and find the '2' char
http://ascii.cl/index.htm?content=mobile

Convert int to char in java

Below is a code snippet,
int a = 1;
char b = (char) a;
System.out.println(b);
But what I get is empty output.
int a = '1';
char b = (char) a;
System.out.println(b);
I will get 1 as my output.
Can somebody explain this? And if I want to convert an int to a char as in the first snippet, what should I do?
int a = 1;
char b = (char) a;
System.out.println(b);
will print out the char with Unicode code point 1 (start-of-heading char, which isn't printable; see this table: C0 Controls and Basic Latin, same as ASCII)
int a = '1';
char b = (char) a;
System.out.println(b);
will print out the char with Unicode code point 49 (one corresponding to '1')
If you want to convert a digit (0-9), you can add 48 to it and cast, or something like Character.forDigit(a, 10);.
If you want to convert an int seen as a Unicode code point, you can use Character.toChars(48) for example.
My answer is similar to jh314's answer but I'll explain a little deeper.
What you should do in this case is:
int a = 1;
char b = (char)(a + '0');
System.out.println(b);
Here, we used '0' because chars are actually represented by ASCII values. '0' is a char and represented by the value of 48.
We typed (a + '0') and in order to add these up, Java converted '0' to its ASCII value which is 48 and a is 1 so the sum is 49. Then what we did is:
(char)(49)
We casted int to char. ASCII equivalent of 49 is '1'. You can convert any digit to char this way and is smarter and better way than using .toString() method and then subtracting the digit by .charAt() method.
It seems like you are looking for the Character.forDigit method:
final int RADIX = 10;
int i = 4;
char ch = Character.forDigit(i, RADIX);
System.out.println(ch); // Prints '4'
There is also a method that can convert from a char back to an int:
int i2 = Character.digit(ch, RADIX);
System.out.println(i2); // Prints '4'
Note that by changing the RADIX you can also support hexadecimal (radix 16) and any radix up to 36 (or Character.MAX_RADIX as it is also known as).
int a = 1;
char b = (char) a;
System.out.println(b);
hola, well i went through the same problem but what i did was the following code.
int a = 1
char b = Integer.toString(a).charAt(0);
System.out.println(b);
With this you get the decimal value as a char type. I used charAt() with index 0 because the only value into that String is 'a' and as you know, the position of 'a' into that String start at 0.
Sorry if my english isn't well explained, hope it helps you.
you may want it to be printed as '1' or as 'a'.
In case you want '1' as input then :
int a = 1;
char b = (char)(a + '0');
System.out.println(b);
In case you want 'a' as input then :
int a = 1;
char b = (char)(a-1 + 'a');
System.out.println(b);
java turns the ascii value to char :)
int a = 1;
char b = (char) (a + 48);
In ASCII, every char have their own number. And char '0' is 48 for decimal, '1' is 49, and so on. So if
char b = '2';
int a = b = 50;
Nobody has answered the real "question" here: you ARE converting int to char correctly; in the ASCII table a decimal value of 01 is "start of heading", a non-printing character. Try looking up an ASCII table and converting an int value between 33 and 7E; that will give you characters to look at.
Whenever you type cast integer to char it will return the ascii value of that int (once go through the ascii table for better understanding)
int a=68;
char b=(char)a;
System.out.println(b);//it will return ascii value of 68
//output- D
If we are talking about class types - not primitives, the following trick has to be done:
Integer someInt;
Character someChar;
someChar = (char)Integer.parseInt(String.valueOf(someInt));
First, convert the int (or another type) to String,
int a = 1;
String value = String.valueOf(a);
Then, convert that String to char.
char newValue = value.charAt(0);
You can avoid empty output in this way...
System.out.println(newValue);
In java a char is an int. Your first snippet prints out the character corresponding to the value of 1 in the default character encoding scheme (which is probably Unicode). The Unicode character U+0001 is a non-printing character, which is why you don't see any output.
If you want to print out the character '1', you can look up the value of '1' in the encoding scheme you are using. In Unicode this is 49 (the same as ASCII). But this will only work for digits 0-9.
You might be better off using a String rather than a char, and using Java's built-in toString() method:
int a = 1;
String b = toString(a);
System.out.println(b);
This will work whatever your system encoding is, and will work for multi-digit numbers.
if you want to print ascii characters based on their ascii code and do not want to go beyond that (like unicode characters), you can define your variable as a byte, and then use the (char) convert. i.e.:
public static void main(String[] args) {
byte b = 65;
for (byte i=b; i<=b+25; i++) {
System.out.print((char)i + ", ");
}
BTW, the ascii code for the letter 'A' is 65
Make sure the integer value is ASCII value of an alphabet/character.
If not then make it.
for e.g. if int i=1
then add 64 to it so that it becomes 65 = ASCII value of 'A'
Then use
char x = (char)i;
print x
// 'A' will be printed
There is one method by which int can be converted to char and even without using ASCII values.
Example:
int i = 2;
char ch = Integer.toString(i).charAt(0);
System.out.println(ch);
Explanation :
First the integer is converted to string and then by using String function charAt(), character is extracted from the string. As the integer only has one single digit, the index 0 is given to charAt() function.
My solution is for converting lower case alphabets (a-z) to (0-25) and vice versa.
My answer is for a specific use-case it is not generic solution my solution will help you if you want to store the frequency of character into an integer array of size 26 instead of using Hashmap<Character,Integer>
----> for converting 0 to 25 into a-z
char ch=(char)(0+'a'); // output 'a' // input 0(as integer)
char ch=(char)(25+'a'); // output 'z' // input 25(as integer)
---->for converting a to z into 0-25
int freq='a'-'a' // output 0 // input 'a'
int freq='b'-'a' // output 1 // input 'b'
int freq='c'-'a' // output 2 // input 'c'
int freq='z'-'a' // output 25 // input 'z'
Again this approach will help you to get the frequency of characters as well as characters
public class Main
{
public static void main(String[] args) {
String s="rajatfddfdf";
int freq[]= new int[26];
for(int i=0;i<s.length();i++){
char characterAtIndex=s.charAt(i);
freq[characterAtIndex-'a']+=1;
}
for(int i=0;i<26;i++){
System.out.println((char)('a'+i)+" frequency="+freq[i]);
}
}
}
by using the above code we can get the frequency as well as character using integer array of size 26 . We can write if-else logic if you don't want to include the character with frequency 0.
look at the following program for complete conversion concept
class typetest{
public static void main(String args[]){
byte a=1,b=2;
char c=1,d='b';
short e=3,f=4;
int g=5,h=6;
float i;
double k=10.34,l=12.45;
System.out.println("value of char variable c="+c);
// if we assign an integer value in char cariable it's possible as above
// but it's not possible to assign int value from an int variable in char variable
// (d=g assignment gives error as incompatible type conversion)
g=b;
System.out.println("char to int conversion is possible");
k=g;
System.out.println("int to double conversion is possible");
i=h;
System.out.println("int to float is possible and value of i = "+i);
l=i;
System.out.println("float to double is possible");
}
}
hope ,it will help at least something
If you want to convert a character to its corresponding integer, you can do something like this:
int a = (int) 'a';
char b = (char) a;
System.out.println(b);
This happens because in ASCII there are some items that can not be printed normally.
For example, numbers 97 to 122 are integers corresponding to the lowercase letters a to z.
public class String_Store_In_Array
{
public static void main(String[] args)
{
System.out.println(" Q.37 Can you store string in array of integers. Try it.");
String str="I am Akash";
int arr[]=new int[str.length()];
char chArr[]=str.toCharArray();
char ch;
for(int i=0;i<str.length();i++)
{
arr[i]=chArr[i];
}
System.out.println("\nI have stored it in array by using ASCII value");
for(int i=0;i<arr.length;i++)
{
System.out.print(" "+arr[i]);
}
System.out.println("\nI have stored it in array by using ASCII value to original content");
for(int i=0;i<arr.length;i++)
{
ch=(char)arr[i];
System.out.print(" "+ch);
}
}
}

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