1 public class Solution { 2     public int[][] multiply(int[][] A, int[][] B) { 3         int aM = A.length, aN = A[0].length,  bN = B[0].length; 4         int [][] result = new int[aM][bN]; 5         for (int i = 0; i < aM; i++) { 6             for (int j = 0; j < aN; j++) { 7                 if (A[i][j] != 0) { 8                     for (int k = 0; k < bN; k++) { 9                         if (B[j][k] != 0) {10                             result[i][k] += A[i][j] * B[j][k];11                         }12                     }13                 }14             }15         }16         return result;17     }18 }