#include "stdio.h"
main()
{
int x,y,z;
for(x=1;x<=20;x++)
    for(y=1;y<=33;y++)
        for(z=3;z<=99;z+=3)
        {
          if((5*x+3*y+z/3==100)&&(x+y+z==100))
          printf("公鸡=%d,母鸡=%d,小鸡=%d\n",x,y,z);
        }
}

还有简单的？