求解决C语言数组的问题

萌新一枚

#include <stdio.h>

int main()
{
    int a[3][3] = {1, 2, 3, 4, 5, 6, 7, 8, 9};
    int i, j, t;
    for (i = 0; i < 3; i++)
        for (j = 0; j < i; j++)
        {
            t = a[i][j];
            a[i][j] = a[j][i];
            a[j][i] = t;
        }
    for (i = 0; i < 3; i++)
    {
        for (j = 0; j < 3; j++)
            printf("%3d", a[i][j]);
        printf("\n");
    }
    return 0;
}