我如何获得 Java 中二维数组的最小总和？

Question

I have this code, which calculates the sum of all rows in 2D array but I want to print the smallest sum of rows also.

Here down is my code:

package com.example;

import java.util.Arrays;

public class discrete2 {

    public static void main(String[] args) {

        int a[][] = {
                {0, 1, 1, 0, 1, 0, 0, 1, 0},
                {1, 0, 1, 1, 0, 0, 0, 1, 0},
                {1, 0, 0, 1, 0, 1, 1, 0, 1},
                {0, 1, 0, 0, 0, 1, 0, 0, 1},
                {0, 0, 1, 1, 0, 0, 0, 0, 1},
                {1, 0, 0, 0, 0, 0, 1, 1, 0},
                {0, 0, 0, 0, 1, 1, 1, 0, 0}
        };

        int rows = a.length;
        int cols = a[0].length;

        int sumCol;

        for(int i = 0; i < cols; i++){
            sumCol = 0;
            for(int j = 0; j < rows; j++){
                sumCol = sumCol + a[j][i];
            }
            System.out.println("Sum of " + (i+1) +" column: " + sumCol);
        }
    }
}

I tried to changing my code to have variable that remembers the smallest number but it's not working somehow and gives out 3, when it should be 2.

Answer 1

public static void main(String[] args) {
    int a[][] = {
            {0, 1, 1, 0, 1, 0, 0, 1, 0},
            {1, 0, 1, 1, 0, 0, 0, 1, 0},
            {1, 0, 0, 1, 0, 1, 1, 0, 1},
            {0, 1, 0, 0, 0, 1, 0, 0, 1},
            {0, 0, 1, 1, 0, 0, 0, 0, 1},
            {1, 0, 0, 0, 0, 0, 1, 1, 0},
            {0, 0, 0, 0, 1, 1, 1, 0, 0}
    };

    int rows = a.length;
    int cols = a[0].length;

    int sumCol;
    int minSumCol = 100000000; // arbitrary large value

    for (int i = 0; i < cols; i++) {
        sumCol = 0;
        for (int j = 0; j < rows; j++) {
            sumCol = sumCol + a[j][i];
        }
        minSumCol = Math.min(minSumCol, sumCol);
        System.out.println("Sum of " + (i + 1) + " column: " + sumCol);
    }
    System.out.println("Min sum in the matrix is: " + minSumCol);
}

Hi, your code is indeed correct. It does return 2 as the smallest value. This is the output that I got:

Sum of 1 column: 3

Sum of 2 column: 2

Sum of 3 column: 3

Sum of 4 column: 3

Sum of 5 column: 2

Sum of 6 column: 3

Sum of 7 column: 3

Sum of 8 column: 3

Sum of 9 column: 3

Min sum in the matrix is: 2