KWeakestRows.java

import java.util.Arrays;

public class KWeakestRows {
   

    static int[] kWeakest(int [][]mat, int k) {
        int m = mat.length;
        int n = mat[0].length;
        int pairs[][] = new int[m][2];
        for(int i = 0; i < m; i++) {
            int strength = 0;
            for(int j = 0; j < n; j++) {
                if(mat[i][j] == 0) {
                    break;
                }
                strength++;
            }
            pairs[i][0] = strength;
            pairs[i][1] = i;
        }
        Arrays.sort(pairs, (a,b) -> {
            if(a[0] == b[0]) return a[1] - b[1];
            else return a[0] - b[0];
        });

        int []indexes = new int[k];
        for(int i = 0; i < k; i++) {
            indexes[i] = pairs[i][1];
        }
        return indexes;
    }

    public static void main(String[] args) {
        int mat[][] = {{1,1,0,0,0},
                        {1,1,1,1,0},
                        {1,0,0,0,0},
                        {1,1,0,0,0},
                        {1,1,1,1,1}};
        int k = 3;
        int output[] = kWeakest(mat, k);
        for(int i = 0; i < output.length; i++) {
            System.out.println(output[i]);
        }
    }
 }