运行时错误_字符串索引超出范围异常_打印字符串奇偶索引

Question

Code:

import java.io. ; import java.util. ;

public class Solution {

public static void main(String[] args) {
    
    Scanner sc = new Scanner(System.in);

    int n = sc.nextInt();
    String[] sa = new String[n];
    for(int i=0;i<n;i++){

        sa[i] = sc.nextLine();
    }
        String odd="";
        String even="";
        for(int i=0;i<n;i++)
        {
            for(int j=0;j<sa[i].length();j++)
            {
             if(j%2!=0){
               odd = odd+sa[j].charAt(j);
            }
            else {
                even = even+sa[j].charAt(j);
            }
       
            }
            System.out.println(odd+" "+even);
            }
}

}

ISsue: GEtting run time exception while running the code. --> String index out of bound exception

Answer 1

You can try below code. It is because of calling a method like nextInt() before sc.nextLine()

The problem is that nextInt() does not consume the '\n', so the next call to nextLine() consumes it and then it's waiting to read the input for next element.

You need to consume the '\n' before calling nextLine() or You can directly call nextLine() for array size as well.

public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter Array size");
        int n = Integer.parseInt(sc.nextLine());
        String[] sa = new String[n];
        for (int i = 0; i < n; i++) {
            System.out.println("Enter Element "+i);
            String val = sc.nextLine();
            sa[i]=val;
        }
        String odd = "";
        String even = "";
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < sa[i].length(); j++) {
                if (j % 2 != 0) {
                    odd = odd + sa[j].charAt(j);
                } else {
                    even = even + sa[j].charAt(j);
                }

            }
            System.out.println(odd + " " + even);
        }
    }