关于C语言程序设计的题

写源程序

 
#include <stdio.h>
int main(int argc, char**argv)
{
    int a[3][4];
    ///初始化
    printf("输入3*4矩阵：\n");
    for (int i = 0; i < 3;i++)
    {
        for (int j = 0; j < 4;j++)
        {
            scanf("%d", &a[i][j]);
        }
    }
    //找最大元素并交换
    int max ,index,t;
    for (int i = 0; i < 3;i++)
    {
        index = 0;
        max = a[i][0];
        for (int j = 0; j < 4;j++)
        {
            if(a[i][j]>max)
            {
                max = a[i][j];
                index = j;
            }
        }
        if(index!=0)
        {
            t = a[i][0];
            a[i][0] = a[i][index];
            a[i][index] = t;
        }
    }
    //输出矩阵
    printf("交换后的3*4矩阵：\n");
    for (int i = 0; i < 3;i++)
    {
        for (int j = 0; j < 4;j++)
        {
            printf("%d ", a[i][j]);
        }
        printf("\n");
    }
 
    return 0;
}