zzulioj1128课程平均分 为什么在idea编译正确在 OJ 提交时运行错误？

Question

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        int m = s.nextInt();
        int n = s.nextInt();
        double[][] a = new double[m][n];
        double[] b = new double[m];
        for (int i = 0; i < m; i++) {
            for (int j = 0; j < n; j++) {
                a[i][j] = s.nextDouble();
            }
        }
        for (int j = 0; j < n; j++) {
            double f = 0;
            for (int i = 0; i < m; i++) {
                f += a[i][j];
            }
            b[j] = f / m;
            System.out.printf("%.2f", b[j]);
            System.out.print(" ");
        }
    }
}