import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int N = sc.nextInt(); int M = sc.nextInt(); int[][] A = new int[N][M]; for (int i = 0; i < N; i++) { for (int j = 0; j < M; j++) { A[i][j] = sc.nextInt(); } } int res = 0; for (int i = 0; i < M; i++) { int max = Integer.MIN_VALUE; for (int j = 0; j < N; j++) { max = Math.max(max, A[j][i]); } res += max; } System.out.println(res); } } 第二题看是其他人发的帖子 import java.util.Arrays; import java.util.Scanner; public class Main2 { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); int[] nums = new int[n]; for (int i = 0; i < n; i++) nums[i] = sc.nextInt(); int sum = 0; int flag = 0; for (int i = 0; i < n; i++) { if (nums[i] < 0) { flag = 1; } else { sum += nums[i]; } } if (flag == 1) { Arrays.sort(nums); int max = nums[nums.length - 1]; sum -= max; } System.out.println(sum); } }