编写一个程序实现以下内容

  1 #include <stdio.h>
  2 
  3 int main()
  4 {
  5     int arr[3][4] = {0};
  6 
  7     /* 给数组赋值 */
  8     for (int i = 0; i < 3; i++) {
  9         scanf("%d %d %d %d",
 10                 arr[i], arr[i] + 1, arr[i] + 2, arr[i] + 3);
 11     }
 12 
 13     /* 判断 */
 14     for (int i = 0; i < 3; i++) {
 15         for (int j = 0; j < 4; j++) {
 16             if (arr[i][j] < 0) {
 17                 printf("arr[%d][%d] < 0\n", i, j);
 18             }
 19         }
 20     }
 21 
 22     return 0;
 23 }