I know how to sort integers and how to convert a character into an ASCII code but I'm having some trouble how to put them together.
Basically I have this code that turns String to ASCII. But I'd like to use selection sort after it prints or before it prints. Do you know how?
public static void main (String [] args)throws IOException{
BufferedReader input = new BufferedReader (new InputStreamReader (System.in));
System.out.println("Enter Full Name: ");
String str = input.readLine();
for (int i = 0; i < str.length(); i++){
char c = str.charAt(i);
int k = (int) c;
System.out.println(c + " = " + k);
}
}
}
I have gone through your issue. I have updated your source code and it is working as you expected.
Note few points :
Maintain an array to store ASCII values.
Print this array before selection Sort.
Call selectionSort method for sorting.
Print this array after selection sort.
Just copy paste this code should work.
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class StackOverflow {
public static void main(String[] args) throws IOException {
BufferedReader input = new BufferedReader (new InputStreamReader (System.in));
System.out.println("Enter Full Name: ");
String str = input.readLine();
int[] array = new int[str.length()];;
for (int i = 0; i < str.length(); i++){
char c = str.charAt(i);
int k = (int) c;
array[i] = k;
}
System.out.println("Before Selection Sort");
for(int i:array){
System.out.print(i+" ");
}
System.out.println();
selectionSort(array);//sorting array using selection sort
System.out.println("After Selection Sort");
for(int i:array){
System.out.print(i+" ");
}
}
public static void selectionSort(int[] arr){
for (int i = 0; i < arr.length - 1; i++)
{
int index = i;
for (int j = i + 1; j < arr.length; j++){
if (arr[j] < arr[index]){
index = j;//searching for lowest index
}
}
int smallerNumber = arr[index];
arr[index] = arr[i];
arr[i] = smallerNumber;
}
}
}
ouput:
Enter Full Name:
ramesh
Before Selection Sort
114 97 109 101 115 104
After Selection Sort
97 101 104 109 114 115
Try storing the k values in an integer array of the same length as the string.
Then apply selection sort on it.
Like:
public static void main (String [] args)throws IOException{
BufferedReader input = new BufferedReader (new InputStreamReader (System.in));
System.out.println("Enter Full Name: ");
String str = input.readLine();
int[] str_ascii = new int[str.length()];
for (int i = 0; i < str.length(); i++){
char c = str.charAt(i);
int k = (int) c;
str_ascii[i] = k;
System.out.println(c + " = " + k);
}
//now selection sort the array str_ascii
}
}
Question
Given a string S of length N, that is indexed from 0 to N-1, print it's even indexed and odd indexed characters as 2 space separated strings on a single line.
Assume input starts at index position 0(which is considered even)
Input
The first line contains an integer, T (the number of test cases).
Each line i of the T subsequent lines contain a String, S.
Output
For each string S, print it's even-indexed characters, followed by space, followed by odd-indexed characters.
Sample Input
2
Hacker
Rank
Sample Output
Hce akr
Rn ak
The Code I Wrote
public static void main(String[] args)
{
Scanner scan = new Scanner(System.in);
int T = scan.nextInt();
scan.nextLine();
for(int i=0 ; i<T ; i++)
{
String myString = scan.nextLine();
int evn = 0,
odd = 0,
len = myString.length();
char strE[] = new char[50],
strO[] = new char[50];
for(int j=0 ; j<len ; j++)
{
if(j%2 == 0)
{
strE[evn] = myString.charAt(j);
evn++;
}
if(j%2 == 1)
{
strO[odd] = myString.charAt(j);
odd++;
}
}
System.out.print(strE);
System.out.print(" ");
System.out.println(strO);
}
}
My Output
Hce akr
Rn ak
The Problem
As you can see, my program successfully meets the test case, and other test cases (using custom input) but every time the HackerRank compiler tells me that my program did not meet the test case.
Clearly, my program is producing the required output but every time the HackerRank compiler tells me that I got the solution wrong.
Could anyone please tell me where I am making a mistake?
Further Modifications
I then decided to change the last 3 lines of print statements into one statement as follows:
System.out.println(strE + " " + strO);
However, this time the program did not produce the desired output and rather printed some garbage values as follows:
[C#5c3f3b9b [C#3b626c6d
[C#3abc8690 [C#2f267610
My Doubts
1. In the first case, when I was printing the two strings separately using 2 print statements, I was getting a correct output everytime but the HackerRank compiler rejected it. Why?
2. In the second case, when I modified the program by using one print statement instead of 3 to get the desired result, the program gave a completely different output and rather printed garbage values! Why?
Here is a link to the HackerRank problem for more info:
hackerrank.com/challenges/30-review-loop
All help and guidance is greatly appreciated and thanks a lot in advance!
Try to submit this:
Scanner scan = new Scanner(System.in);
int T = scan.nextInt();
scan.nextLine();
for (int i = 0; i < T; i++) {
String myString = scan.nextLine();
String even = "";
String odd = "";
for (int j = 0; j < myString.length(); j++) {
if (j % 2 == 0) {
even += myString.charAt(j);
} else {
odd += myString.charAt(j);
}
}
System.out.println(even + " " + odd);
}
i get the right output and it should meet all the requirements. i think your code fails because its not a real string you print in the end and you have empty spots in your arrays
Scanner scanner = new Scanner(System.in);
System.out.println("Enter the no.of test-cases:");
int t = scanner.nextInt();
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter the String(s)");
for (int i = 0; i < t; i++) {
String myString = br.readLine();
String even = "";
String odd = "";
for (int j = 0; j < myString.length(); j++) {
if (j % 2 == 0) {
even += myString.charAt(j);
} else {
odd += myString.charAt(j);
}
}
System.out.println(even);
System.out.println(odd);
}
scanner.close();
int T = scan.nextInt();
This reads quantity of test cases, which we're going to process.
String string[] = new String[T];
for(int i = 0; i<T; i++){
string[i] = scan.next();
}
Next we're creating an array named "string" (BTW, this a bad name for variables/objects) which has size T and in the for loop reading test cases from the input T times and saving them in the array.
for(int temp = 0; temp<T; temp++){
Now, for each of test cases we do the following...
for(int j = 0; j<string[temp].length(); j = j+2)
{
System.out.print(string[temp].charAt(j));
}
We create a local variable j, which is visible only in this for loop. j holds index of the string (=string[temp]), which we're processing. So, we're printing a character on position j (by using standard method "charAt" of String class, which returns character of given index of the string) and then increasing it by 2. So, this code will print every even character. For string "example", it will print "eape" (j=0, j=2, j=4, j=6).
System.out.print(" ");
Separating sequences with a space.
for(int j = 1; j<string[temp].length(); j = j+2){
System.out.print(string[temp].charAt(j));
}
System.out.println();
We're doing the same (creating index j, running though all characters of the string), but starting from "1", so it will print all odd characters of the string. For string "example", it will give you "xml" (j=1, j=3, j=5). and After this, it will end the string. I hope, it will help you to understand. :)
I can solve your the second question:
---> System.out.print(strE);-->At the bottom, the method is called( public void print(char s[]));
-->System.out.println(strE + " " + strO);-->At the bottom, the method is called (public void println(String x) )
For your first answer I am unable to answer you as I have no idea about how the compiler works, but I can answer your second question.
The reason why System.out.print(strE); System.out.print(" "); System.out.println(strO); works is because System.out.print(char[]) and System.out.println(char[]) automatically turn the char arrays into a readable string before printing it.
However, in the second case System.out.println(strE + " " + strO);, what you are doing is directly turning the char array into strings, which just prints the class and the hash code of the array object because the toString() method is not overriden in the array class. What you want to do is System.out.println(new String(strE) + " " + new String(strO));. It will give you the result you want.
import java.io.*;
import java.util.*;
public class Solution {
private static void f(String s) {
// TODO Auto-generated method stub
char c[]=s.toCharArray();
int i,j;
for (i = 0; i <c.length;i++){
System.out.print(c[i]);
i+=1;
}
System.out.print(" ");
for (j = 1; j<c.length;j++){
System.out.print(c[j]);
j+=1;
}
}
public static void main(String[] args){
// TODO Auto-generated method stub
Scanner sc=new Scanner(System.in);
int s=sc.nextInt();
while(hasNext()){
//for loop for multiple strings as per the input
for(int m=0;m<= s;m++){
String s1=sc.next();
f(s1);
System.out.println();
}
}
}
}
I've solved this question in 2 ways & both are producing correct output.
Have a look & let me know if you've any problem.
Instead of using char array, you can use String
//char[] even = new char[10000];
String even = "";
Let's look at the code
private static Scanner scanner = new Scanner(System.in);
public static void main(String[] args) {
String s = scanner.next();
char[] array = s.toCharArray();
int count=0;
//char[] even = new char[10000];
//char[] odd = new char[10000];
String even = "";
String odd = "";
for(char ch : array){
if(count%2 == 0){
even = even + ch;
}else{
odd = odd + ch;
}
count++;
}
count = 0;
System.out.println(even + " " + odd);
}
Output:
hacker
hce akr
No need of extra char[] or String to store even & odd position characters, we can directly print them using appropriate condition.
private static Scanner scanner = new Scanner(System.in);
public static void main(String[] args){
String s = scanner.next();
char[] array = s.toCharArray();
int count=0;
for(char ch : array){
if(count%2 == 0){
System.out.print(ch);
}
count++;
}
count = 0;
System.out.print(" ");
for(char ch : array){
if(count%2 != 0){
System.out.print(ch);
}
count++;
}
count = 0;
}
Output:
hacker
hce akr
Try this:
public static void main(String[] args) {
System.out.println("Enter string to check:");
Scanner scan = new Scanner(System.in);
String T = scan.nextLine();
String even = "";
String odd = "";
for (int j = 0; j < T.length(); j++) {
if (j % 2 == 0) { //check the position of the alphabet by dividing it by 0
even += T.charAt(j);
} else {
odd += T.charAt(j);
}
}
System.out.println(even + " " + odd);
scan.close();
}
** JavaScript version **
function processData(input) {
for (let i = 1; i < input.length; i++) {
printOutput(input[i]);
}
}
function printOutput(input) {
var result = [];
input.length % 2 == 0 ? result[input.length / 2] = ' ': result[Math.ceil(input.length / 2)] = ' ';
for (let i = 0; i < input.length; i++) {
if (i % 2 == 0) {
result[i / 2] = input[i];
}
else {
result[Math.ceil(input.length / 2) + Math.ceil(i / 2)] = input[i];
}
}
console.log(result.join(''));
}
process.stdin.on("end", function () {
processData(_input.split('\n'));
});
import java.io. * ;
import java.util. * ;
public class Solution {
String myString;
public Solution(String myString) {
this.myString = myString;
int len = myString.length();
for (int j = 0; j < len; j++) {
if (j % 2 == 0) {
System.out.print(myString.charAt(j));
}
}
System.out.print(" ");
for (int j = 0; j < len; j++) {
if (j % 2 == 1) {
System.out.print(myString.charAt(j));
}
}
}
public static void main(String[] args) {
/* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
Scanner sc = new Scanner(System. in );
int T = sc.nextInt();
for (int i = 0; i < T; i++) {
String word = sc.next();
Solution sol = new Solution(word);
System.out.println();
}
sc.close();
}
}
import java.io.*;
import java.util.*;
public class Solution {
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
int T;
T = s.nextInt();
String[] str = new String[T];
int i;
for(i=0;i<T;i++) {
str[i] = s.next();
}
for(i=0;i<T;i++) {
char[] even = new char[5000];
char[] odd = new char[5000];
int ev =0,od=0;
for(int j= 0;j< str[i].length();j++) {
if(j%2== 0) {
even[ev] = str[i].charAt(j);
ev++;
}else {
odd[od] = str[i].charAt(j);
od++;
}
}
String strEven = new String(even);
String strOdd = new String(odd);
System.out.print(strEven.trim());
System.out.print(" ");
System.out.println(strOdd.trim());
}
s.close();
}
}
I am sure that this will work You've forgotten to convert it to a string and also increase the size of the character array
import java.io.*;
import java.util.*;
public class Solution {
public static void main(String[] args) {
Scanner scan= new Scanner(System.in);
int n= scan.nextInt();
for(int i=0;i<n;i++){
String s= scan.next();
int len= s.length();
StringBuffer str_e= new StringBuffer();
StringBuffer str_o= new StringBuffer();
for(int j=0;j<len;j++){
if(j%2==0)
str_e= str_e.append(s.charAt(j));
if(j%2==1)
str_o= str_o.append(s.charAt(j));
}
System.out.println(str_e+" "+str_o);
}
}
}
Try this:
import java.io.*;
import java.util.*;
public class Solution {
public static void main(String[] args) {
/* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
Scanner pp=new Scanner(System.in);
int n=pp.nextInt();
for(int i=0; i<n; i++)
{
String ip=pp.next();
String re1="",
re2="";
for(int j=0; j<ip.length(); j++)
{
if(j%2 == 0)
{
re1+= ip.charAt(j);
}
if(j%2 == 1)
{
re2+= ip.charAt(j);
}
}
System.out.print(re1+" "+re2);
System.out.println("");
}
}
}
public class PrintCharacters{
public static void main(String args[]) {
Scanner sc = new Scanner(System.in);
int noOfTestCases = sc.nextInt();
sc.nextLine();
String []inputStrings= new String[noOfTestCases];
for(int i=0;i<noOfTestCases;i++) {
inputStrings[i]=sc.nextLine();
}
for(String str: inputStrings) {
String even ="";
String odd ="";
for(int i=0;i<str.length();i++) {
if(i%2==0) {
even+=str.charAt(i);
}else {
odd+=str.charAt(i);
}
}
System.out.println(even+" "+odd);
}
sc.close();
}
}
Input:
2
Hacker
Rank
Output:
Hce akr
Rn ak
import java.util.*;
public class Solution {
public static void main(String[] args) {
/* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
Scanner scan=new Scanner(System.in);
int n=scan.nextInt();
while(n>0) {
String str=scan.next();
for(int i=0;i<str.length();i++) {
if(i%2==0) {
System.out.print(str.charAt(i));
}
}
System.out.print(" ");
for(int i=0;i<str.length();i++) {
if(i%2==1) {
System.out.print(str.charAt(i));
}
}
n--;
System.out.println();
}
}
}
I've been working on this program and am currently stuck. The HW prompt is to prompt a user to input numbers, save it as an array, find the number of odd numbers & the percentages then display those values back to the user.
Currently I am trying to write to part of the code that finds the percentage of the odd numbers in the array but the return isn't displaying and i just cant figure it out. Any ideas? Thank you!
import java.util.*; // import java course for Scanner class
public class Integers {
public static void main(String[] args) {
Scanner console = new Scanner(System.in);
System.out.println("Please input a series of numbers");
int inputs = Integer.parseInt(console.next());
int[] arraysize = new int[inputs];
Oddvalues(arraysize);
}
public static int Oddvalues (int[] size) {
int countOdd = 0;
for (int i = 1; i < size.length; i++) {
if(size[i] % 2 != 0) {
i++;
}
}
return countOdd;
}
}
Consider the following code, which appears to be working in IntelliJ locally. My approach is to read in a single line from the scanner as a string, and then to split that input by whitespace into component numbers. This avoids the issue you were facing of trying to directly create an array of integers from the console.
Then, just iterate over each numerical string, using Integer.parseInt(), checking to see if it be odd.
public static void main(String[] args) {
Scanner console = new Scanner(System.in);
System.out.println("Please input a series of numbers");
String nextLine = console.nextLine();
String[] nums = nextLine.split(" ");
int oddCount = 0;
for (String num : nums) {
if (Integer.parseInt(num) % 2 == 1) {
++oddCount;
}
}
double oddPercent = 100.0*oddCount / nums.length;
System.out.println("Total count of numbers: " + nums.length + ", percentage odd: " + oddPercent);
}
In the function Oddvalues you promote i instead of promoting countOdd. And the loop should start from 0 not 1.
Try this
import java.util.*;
import java.lang.*;
import java.io.*;
public class OddVals{
public static void main(String[] args) throws java.lang.Exception {
Scanner sc = new Scanner(System.in);
int[] array = new int[sc.nextInt()]; // Get the value of each element in the array
System.out.println("Please input a series of numbers");
for(int i = 0; i < array.length; i++)
array[i] = sc.nextInt();
System.out.println("Number of Odds:" +Oddvalues(array));
printOdd(array);
}
public static int Oddvalues (int[] size) {
int countOdd = 0;
for (int i=0; i < size.length; i++){
if(size[i]%2 != 0)
++countOdd;
}
return countOdd;
}
public static void printOdd(int[] arr)
{
for(int i=0;i<arr.length;++i)
{
if(arr[i]%2==1)
System.out.print(arr[i]+" ");
}
}
import java.util.*; // import java course for Scanner class
public class Integers {
public static void main(String[] args) {
List<Integer> intList = new ArrayList<Integer>();
Scanner console = new Scanner(System.in);
System.out.println("Please input a series of numbers");
while (console.hasNext())
{
String str = console.next();
try
{
if(str.equals("quit")){
break;
}
int inputs = Integer.parseInt(str);
System.out.println("the integer values are" +inputs);
intList.add(inputs);
}
catch (java.util.InputMismatchException|NumberFormatException e)
{
console.nextLine();
}
}
console.close();
double d = Oddvalues(intList);
System.out.println("the percent is" +d);
}
public static double Oddvalues (List<Integer> list) {
int count = 0;
for( Integer i : list)
{
if(!(i%2==0))
{
count++;
}
}
double percentage = (Double.valueOf(String.valueOf(count))/ Double.valueOf(String.valueOf(list.size())))*100;
return percentage;
}
}
If this helps
I am fairly new to Java and I am trying to write a small program that asks a user to enter 3 integers between 1-10, stores them in an array and then adds up the integers and tells the user the answer. I have written this so far and it works:
import java.util.Scanner;
public class Feb11a {
public static void main(String[] args) {
int[] numArr = new int[3];
int sum = 0;
Scanner keyboard = new Scanner(System.in);
System.out.println("Enter 3 numbers in the range 1 to 10: ");
for (int i = 0; i < numArr.length; i++) {
numArr[i] = keyboard.nextInt();
}
for (int counter = 0; counter < numArr.length; counter++) {
sum += numArr[counter];
}
System.out.println("The sum of these numbers is " + sum);
}
}
My problem is I am also meant to validate the input as in if they enter a double, a string or a number outside the 1-10 range. I have tried a while loop but I just cannot get the program to work, below is what I have so far. If I take out the first while loop the second one works i.e. it checks if it is an integer:
import java.util.Scanner;
public class Feb11a {
public static void main(String[] args) {
int[] numArr = new int[3];
int sum = 0;
Scanner keyboard = new Scanner(System.in);
for (int i = 0; i < numArr.length; i++) {
//check if between 1 and 10
while (i > 10 || i < 1) {
System.out.println("Enter a number in the range 1 to 10: ");
//check if integer
while (!keyboard.hasNextInt()) {
System.out.println("Invalid entry, please try again ");
keyboard.next();
}
numArr[i] = keyboard.nextInt();
}
}
for (int counter = 0; counter < numArr.length; counter++) {
sum += numArr[counter];
}
System.out.println("The sum of these numbers is " + sum);
}
}
My question is how do I get it to check if it is an integer and if it is the range 1-10?
import java.util.Scanner;
public class NewClass {
public static void main(String[] args)
{
int[] numArr = new int[3];
int sum=0,x;
Scanner keyboard = new Scanner(System.in);
for(int i=0; i<numArr.length; i++)
{
//check if between 1 and 10
System.out.println("Enter a number in the range 1 to 10: ");
//check if integer
while (!keyboard.hasNextInt())
{
System.out.println("Invalid entry, please try again ");
keyboard.next();
}
x = keyboard.nextInt();
if(x>0 && x<=10)
numArr[i]=x;
else{
System.out.println("Retry Enter a number in the range 1 to 10:");
i--;
}
}
for (int counter=0; counter<numArr.length; counter++)
{
sum+=numArr[counter];
}
System.out.println("The sum of these numbers is "+sum);
}
}
To check simple use Integer.parseInt() and catch the NumberFormatException (together with Scanner.next()).
Once format is correct you can do an int comparison (i>0 && i<11).
I suggest you to use NumberUtils under org.apache.commons.lang.math
It has isDigits method to check whether given string contains only digits or not:
if (NumberUtils.isDigits(str) && NumberUtils.toInt(str) < 10) {
// your requirement
}
Note that toInt returns zero for big numbers!
Maybe for just this reason adding a whole library seems unnecessary but for bigger projects you will need such libraries like Apache Commons and Guava
You can wrap the System in into a BufferedReader to read whatever the user has to input, then check if its an 'int' and repeat input from user.
I have modified your code a little bit to make it work.
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
public class Feb11a {
public static void main(String[] args) throws NumberFormatException, IOException
// You may want to handle the Exceptions when calling the getInt function
{
Feb11a tester = new Feb11a();
tester.perform();
}
public void perform() throws NumberFormatException, IOException
{
int[] numArr = new int[3];
int sum = 0;
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
for (int i = 0; i < numArr.length; i++)
{
int anInteger = -1;
do
{
// First get input from user.
System.out.println("Enter a number in the range 1 to 10: ");
anInteger = getInt(in);
} while (anInteger > 10 || anInteger < 1); // then check for repeat condition. Not between 1 and 10.
numArr[i] = anInteger; // set the number into the array.
}
for (int counter = 0; counter < numArr.length; counter++)
{
sum += numArr[counter];
}
System.out.println("The sum of these numbers is " + sum);
}
public int getInt(BufferedReader br) throws NumberFormatException, IOException
{
String str = br.readLine();
int toReturn = Integer.parseInt(str);
return toReturn;
}
}
I am working on a program that needs to calculate the sum of 2 large integers without using the biginteger class in java. I am stuck on my for loop which calculates the sum. I am getting an extra 0 so 30 + 30 = 600.
I am pretty sure it is because I am looping through the arrays the wrong way. I need to go the opposite way (starting from the right side like you would when adding numbers) but I can't seem to fix it without getting an out of array index error.
here is my code:
main:
import java.util.Scanner;
public class testLargeInteger
{
public static void main(String[] args)
{
Scanner input = new Scanner(System.in);
String string1;
String string2;
int exp =0;
System.out.print("Enter the first integer: ");
//Store up the input string “string1” entered by the user from the keyboard.
string1 = input.next();
LargeInteger firstInt = new LargeInteger(string1);
System.out.print("Enter the second integer: ");
string2 = input.next();
//Store up the input string “string2” entered by the user from the keyboard.
LargeInteger secondInt = new LargeInteger(string2);
System.out.print("Enter the exponential integer: ");
//Store up the input integer “exp” entered by the user from the keyboard.
exp = input.nextInt();
LargeInteger sum = firstInt.add(secondInt);
System.out.printf ("First integer: %s \n", firstInt.display());
System.out.println("Second integer: " + secondInt.display());
System.out.println(" Exponent: " + exp);
System.out.printf (" Sum = %s \n", sum.display());
}
}
Large integer:
public class LargeInteger {
private int[] intArray;
//convert the strings to array
public LargeInteger(String s) {
intArray = new int[s.length()];
for (int i = 0; i < s.length(); i++) {
intArray[i] = Character.digit(s.charAt(i), 10); // in base 10
}
}
public LargeInteger( int[] array ) {
intArray = array;
}
//display the strings
public String display() {
String result="";
for (int i = 0; i < intArray.length; i++) {
result += intArray[i];
}
return result.toString();
}
//get first array
public int[] getIntArray() {
return intArray;
}
//ADD method to add 2 arrays together
public LargeInteger add(LargeInteger secondInt){
int[] otherValues = secondInt.getIntArray();
int maxIterations = Math.min(intArray.length, otherValues.length);
int currentResult; //to store result
int[] resultArray = new int[Math.max(intArray.length, otherValues.length) +1 ];
int needToAdd = 0; //to store result should be added next step
for(int i = 0; i < maxIterations; i++) {
currentResult = intArray[i] + otherValues[i];
resultArray[i] = currentResult % 10 + needToAdd; //if more than 9 its correct answer
needToAdd = currentResult / 10; //this is what you need to add on next step
}
resultArray[Math.max(intArray.length, otherValues.length) ] = needToAdd;
return new LargeInteger( resultArray );
}
}
I have tried changing the for loop in sum to something like this:
for(int i = maxIterations; i >= 0; i--)
That for loop is only one of your problems.
1] you are not adding the carry properly.
2] a stack is more appropriate here than an array.
With a stack (place code inside your method):
Note: You are calling the function with number.add(num2);
public class LargeInt{
private String number;
public LargeInt(String num){
this.number = num;
}
public String add(String num2){
Stack<Integer> adder = toIntegerStack(this.number);//UPDATE
Stack<Integer> addend = toIntegerStack(num2);//UPDATE
Stack<Integer> result = new Stack<Integer>();
int carry =0;
int tmp = 0;
while(!.adder.isEmpty && !addend.isEmpty()){
tmp = adder.pop()+addend.pop()+carry;
if(tmp > 10){
carry = tmp/10;
tmp%=10;
}else{
carry=0;
}
result.push(tmp);
}//while
while(!adder.isEmpty){
tmp = adder.pop()+carry;
if(tmp > 10){
carry = tmp/10;
tmp%=10;
}else{
carry=0;
}
result.push(tmp);
}//while
while(!addend.isEmpty){
tmp = addend.pop()+carry;
if(tmp > 10){
carry = tmp/10;
tmp%=10;
}else{
carry=0;
}
result.push(tmp);
}//while
//beyond this point the result is your answer
//here convert your stack to string before returning
}
}
UPDATE TO ANSWER COMMENT:
I am also editing above to call this function to fill stacks.
private Stack<Integer> toIntegerStack(String n){
Stack<Integer> stack = new Stack<Integer>();
for(char c: n.toCharArray())
stack.push(c-48);//ASCII
return stack;
}//toStack(String)
If you insist on using array, you must follow the same pattern with your array.
int indexA=0;
int indexB=0;
int[] result = new int[1+A.length>B.length?A.length:B.length];
int indexResult=result.length-1;
while(indexA < A.length && indexB <B.length){//inside is same idea
tmp = A[indexA++] + B[indexB++] + carry;
//... do here as for stacks for tmp and carry
result[indexResult--];
}
while(indexA < A.length){
//do as in stack version
}
while(indexB < B.length){
//do as in stack version
}
Your adding code assumes that the least significant digit is in array[0], but your reading code puts the most significant digit there. You should reverse the array after reading.