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Why below code throwing IllegalFormatConversionException error?

import java.util.*;
import java.lang.*;
import java.io.*;
public class Main
{
public static void main (String[] args) throws java.lang.Exception
{
//your code here
Scanner sc =new Scanner(System.in);
int N=sc.nextInt();
int[] arr=new int[N];
for(int i=0;i<N;i++)
arr[i]=sc.nextInt();
Solution s=new Solution();
s.Answer(arr,N);
}
}
class Solution
{
public void Answer(int [] arr,int N)
{
int p=0,ne=0,z=0,i=0;
while(i<arr.length)
{
if(arr[i]>0)
p++;
else if(arr[i]<0)
ne++;
else z++;
i++;
}
System.out.printf("%1.4f \n", p/N);
System.out.printf("%1.4f \n", ne /N);
System.out.printf("%1.4f\n ", z / N);
}
}
I have written the above code for the question Given an array of integers of size N integers, the task is to find the ratio of positive numbers, negative numbers, and zeros in the array up to four decimal places.
Examples:
Input: a[] = {2, -1, 5, 6, 0, -3} 
Output: 0.5000 0.3333 0.1667 
There are 3 positive, 2 negative, and 1 zero. Their ratio would be positive: 3/6 = 0.5000, negative: 2/6 = 0.3333, and zero: 1/6 = 0.1667.
I compiled the above code but it showing an Illegalformatexception. But I am not getting why it is showing like that.
I checked all syntaxes which I have used in this code. but I couldn't find that problem.
please help me in solving this plus-minus problem.

package ddd;
import java.util.*;
public class Main
{
public static void main (String[] args) throws java.lang.Exception
{
//your code here
Scanner sc =new Scanner(System.in);
int N= sc.nextInt();
int[] arr=new int[N];
for(int i=0;i<N;i++)
arr[i]=sc.nextInt();
Solution s=new Solution();
s.Answer(arr,N);
}
}
class Solution
{
public void Answer(int [] arr,int N)
{
int p=0,ne=0,z=0,i=0;
while(i<arr.length)
{
if(arr[i]>0)
p++;
else if(arr[i]<0)
ne++;
else z++;
i++;
}
System.out.printf("%1.4f \n", p/(float)N);
System.out.printf("%1.4f \n", ne/(float)N);
System.out.printf("%1.4f\n ", z/(float)N);
}
}
I think just converting N to float would solve your problem.

I was trying to find the total no. of digits that appear up till a certain number and my code is going wrong when the input is 10^9

import java.util.*;
import java.io.*;
public class Main {
public static void main(String args[]) throws IOException {
//write your code here
Scanner sc = new Scanner(System.in);
int T = sc.nextInt();
// For each Iteration I am adding the total no. of
// 1's place digits, 10's place digits, 100's place digits, and so on.
for(int i=0;i<T;i++){
int Num = sc.nextInt();
int count = 0;
for(int j=1;j<=Num;j*=10){
count += Num-j+1;
}
System.out.println(count);
}
}
}
Input:
3
100
1000000000
222222222
The output I am seeing:
192
298954307
1888888896
Desired Output:
192
8888888899
1888888896

import java.util.*;
import java.io.*;
public class Main {
public static void main(String args[]) throws IOException {
//write your code here
Scanner sc = new Scanner(System.in);
int T = sc.nextInt();
for(int i=0;i<T;i++){
int Num = sc.nextInt();
long count = 0;
for(int j=1;j<=Num;j*=10){
count += Num-j+1;
}
System.out.println(count);
}
}
}
I just needed to change the count variable from int to long.

how to scan many time by using for function?

import java.util.Scanner;
public class array2 {
public static void main(String[]sef)
{
int a=0;
int number[]=new int[20];
Scanner scan=new Scanner(System.in);
for(a=0;a<number.length;a++); //**i want scan data many time**
{
System.out.println(a+"번째 학생의 숫자를 입력하십시오");
number[a]=scan.nextInt();
}
scan.close();
for(a=0;a<10;a++)
{
System.out.println(number[a]);
}
}
}
i want to input data in arr many time. but i don't know how to do and i don't find answers in my language

I found some bugs in your code and I have added a few things to it. You can have a look at the snippet below.
import java.util.Arrays;
import java.util.Scanner;
public class array2 {
public static void main(String[] args) {
int number[] = new int[5];
Scanner scan = new Scanner(System.in);
for (int a = 0; a < number.length; a++) {
System.out.println(a + "번째 학생의 숫자를 입력하십시오");
System.out.println("Please Enter a number");
number[a] = scan.nextInt();
}
System.out.println(Arrays.toString(number));
scan.close();
}
}

set of integers as input to print sum of their cubes

I am trying to solve this question. I tried many different ways, I get the correct output but the testcases are not passed(I dont know what are those testcases). I cant figure what is wrong.
Question:
Given a set of integers (separated by space), write a program to print the sum of their cubes.
Sample Input:
1 2 3 4 5
Sample Output:
225
Sample Input:
1 2
Sample Output:
9
Solution 2:
import java.io.*;
import java.util.*;
class Test{
public static void main(String []args)
{
int num,sum=0;
Scanner sc=new Scanner(System.in);
String data=sc.nextLine();
Scanner sc2=new Scanner(data);
while(sc2.hasNextInt())
{
num=sc2.nextInt();
sum=sum+num*num*num;
}
System.out.print(sum);
}
}

Your test cases most likely contain large integers as input. Use BigInteger to hold their cubes.

I modified my answer according to your needs. Now it gives sum of cubes of numbers in given input which are separated by spaces. Check this :-
import java.math.BigInteger;
import java.util.ArrayList;
import static java.util.Collections.list;
import java.util.List;
import java.util.Scanner;
public class SumOfCubes {
public static void main(String[] args) {
Scanner in=new Scanner(System.in);
String integers="";
Integer num=0;
BigInteger cube;
BigInteger sum=new BigInteger("0");
System.out.println("Enter Integers seperated by space");
integers=in.nextLine();
List<Integer> list = new ArrayList<Integer>();
for (String s : integers.split("\\s")) {
list.add(Integer.parseInt(s));
}
list.toArray();
for(int i=0;i<list.size();i++){
num=list.get(i);
cube=BigInteger.valueOf(num*num*num);
sum=sum.add(cube);
}
System.out.println("Sum of Cubes of numbers in given input = "+sum);
}
}
Hope it helps.

Update (by Andreas): Added boilerplate imports since #Ash seems unable to figure that out.
If you would like an implementation in more functional style (using Java 8+ streams), here is another suggestion:
import java.math.BigInteger;
import java.util.Arrays;
import java.util.Scanner;
public class Test {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
String line = scan.nextLine();
String[] numbers = line.split("\\s+");
BigInteger sum = Arrays.asList(numbers)
.stream()
.map(BigInteger::new)
.map(bigInteger -> bigInteger.pow(3))
.reduce(BigInteger.ZERO, BigInteger::add);
System.out.println(sum);
}
}
Update: After #Andreas comments, the implementation can be even shorter:
import java.math.BigInteger;
import java.util.Scanner;
import java.util.regex.Pattern;
public class Test {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
String line = scan.nextLine();
BigInteger sum = Pattern.compile("\\s+")
.splitAsStream(line)
.map(s -> new BigInteger(s).pow(3))
.reduce(BigInteger::add)
.orElse(BigInteger.ZERO);
System.out.println(sum);
}
}

I have changed your Solution 2 a little bit. Could you please confirm whether this passes the test or not.
import java.math.BigInteger;
import java.util.Scanner;
public class Test{
public static void main(String []args)
{
BigInteger sum=new BigInteger.ZERO;
Scanner sc=new Scanner(System.in);
String data=sc.nextLine();
Scanner sc2=new Scanner(data);
while(sc2.hasNextInt())
{
BigInteger num=new BigInteger(String.valueOf(sc2.nextInt()));
sum= sum.add(num.multiply(num).multiply(num));
}
System.out.print(sum);
}
}

import java.util.*;
class csum
{
public static void main(String args[])
{
Scanner in=new Scanner(System.in);
long csum=0;
while(in.hasNextInt())
{
csum=csum+(long)Math.pow(in.nextInt(),3);
}
System.out.println(csum);
}
}

public static void main(String args[])
{
long num,count=0;
Scanner in=new Scanner(System.in);
while(in.hasNextInt())
{
num=in.nextInt();
count+=Math.pow(num,3);
}
System.out.println(count);
}
or
public Static vid main(String args[])
{
long count;
Scanner in=new Scanner(System.in);
String s=in.nextLine();
String[] t=s.split(" ");
for(i=0;i<t.length;i++)
{
count+=Math.pow(Integer.parseInt(t[i]),3);
}
System.out.println(count);
}

Used long instead of int. Thanks to Andreas and Matsev for the BigInteger idea.
import java.util.*;
class Test{
public static void main(String []args)
{
long num,sum=0;
Scanner sc=new Scanner(System.in);
String data=sc.nextLine();
Scanner sc2=new Scanner(data);
while(sc2.hasNextInt())
{
num=sc2.nextInt();
sum=sum+num*num*num;
}
System.out.println(sum);
}
}

change a scanner to a char variable instead of a int or double data type

import java.io.*;
import java.util.*;
public class Test
{
public static void main(String args[])
{
Scanner kbr = new Scanner(System.in);
System.out.print("Enter Player's Name: ");
double n = kbr.nextInt();
System.out.print(n);
}
}
Can I change this to
char n = kbr.nextInt()
or
how can I get it to look for a character string instead of an int.

you can do this as alternative:
import java.io.*;
import java.util.*;
public class Test
{
public static void main(String args[])
{
try{
Scanner kbr = new Scanner(System.in);
System.out.print("Enter Player's Name: ");
String n = kbr.readLine();
//int z = Integer.parseInt();
char z = n.charAt(0);
System.out.print(n);
}
catch(IOException e){
System.out.printl("IO ERROR !!!");
System.exit(-1);
}
}
}

Something like this?
import java.io.*;
import java.util.*;
class Test
{
public static void main(String args[])
{
Scanner kbr = new Scanner(System.in);
System.out.print("Enter Player's Name: ");
String n = kbr.nextLine();
System.out.print(n);
}
}

If you wants to get only first character of the typed string then
char c = kbr.next().charAt(0);
works fine.
However it allows to input more than single character but as soon as you hit enter,
it will store first character in char c.
For example
import java.io.*;
import java.util.*;
class Test
{
public static void main(String args[])
{
Scanner kbr = new Scanner(System.in);
System.out.print("Enter Character: ");
char n = kbr.next().charAt(0);
System.out.print(n);
}
}
Input: Hello
Output: H