#include <stdio.h>
int main()
{
int arr[3][3] = { {1,2,3,},{4,5,6},{7,8,9} };
int i, sum;
for (i = 0,sum = 0; i < 3; i++)
{
sum += arr[i][i];
int j = 2 - i;
if (j == i)
break;
sum += arr[i][j];
}
printf("对角线元素之和是：%d", sum);
return 0;
}
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按照你这思路未尝不可，解决的话也很简单，直接将break换成continue就可啦，就能达到避免arr[1][1]的二次相加
按照你的算法，sum=arr[0][0]++arr[0][2]+arr[1][1];
由于i=j;break;
所以最终sum=1+3+5=9;
也就是说这样的话break显然早了