/*写一个函数，将一个3x3的矩阵转置*/
#include<stdio.h>
int main()
{
    void trans(int *p);
    int a[3][3]={1,2,3,4,5,6,7,8,9},i,j,*p;
    printf("%d\n",a);
    p=a;                    //把a的地址给p。这点有问题？？？
    trans(p);
    for(i=0;i<3;i++)
    {    for(j=0;j<3;j++)
            printf("%d ",a[i][j]);
        printf("\n");
    }
    return 0;
}

void trans(int *p)
{
    int i,j,t;
    for(i=0;i<3;i++)
        for(j=0;j<3;j++)
        {
            t=*(p+i*3+j);
            *(p+i*3+j)=*(p+j*3+i);
            *(p+j*3+i)=t;
        }
}


C:\Users\Administrator\Desktop\P291-9.CPP(8) : error C2440: '=' : cannot convert from 'int [3][3]' to 'int *'
        Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
执行 cl.exe 时出错.

P291-9.OBJ - 1 error(s), 0 warning(s)

这样写也不对.....
/*写一个函数，将一个3x3的矩阵转置*/
#include<stdio.h>
int main()
{
    void trans(int *p);
    int a[3][3]={1,2,3,4,5,6,7,8,9},i,j;
    printf("%d\n",a);                    //直接用a作实参
    trans(a);
    for(i=0;i<3;i++)
    {    for(j=0;j<3;j++)
            printf("%d ",a[i][j]);
        printf("\n");
    }
    return 0;
}

void trans(int *p)
{
    int i,j,t;
    for(i=0;i<3;i++)
        for(j=0;j<3;j++)
        {
            t=*(p+i*3+j);
            *(p+i*3+j)=*(p+j*3+i);
            *(p+j*3+i)=t;
        }
}

C:\Users\Administrator\Desktop\P291-9.CPP(8) : error C2664: 'trans' : cannot convert parameter 1 from 'int [3][3]' to 'int *'
        Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
执行 cl.exe 时出错.

P291-9.OBJ - 1 error(s), 0 warning(s)

这两写法错在哪呢？求教。