#include <stdio.h>
void main()
{
    int max(int x,int y,int z);
    int a,b,c,d;
    scanf("%d,%d,%d",&a,&b,&c);
    d=max(a,b,c);
    printf("max=%d\n",d);
}

int max(int x,int y,int z)
{
    int e;
    if (x>y)
    {   if (y>z)
           e=x;
       else //(y<z)
       {   if (x>z) e=x;
            else e=z;
       }
    }
    else //(x<y)
    {   
        if (x>z)
            e=y;
         else //(x<z)
         {     if (y>z)
                e=y;
            else e=z;
         }
    return(e);
    }
}

输出最值.obj : error LNK2005: _main already defined in 比大小.obj
Debug/大小.exe : fatal error LNK1169: one or more multiply defined symbols found
Error executing link.exe.

vc6.0  还是不行哦

哦，谢谢