#include<stdio.h> int max(x,y); main() { int a,b,c; scanf("%d,%d",&a,&b); c=max(x,y); //c=max(a,b); x和y是形参 printf("max=%d",c); } int max(x,y); { int z; if(x>y)z=x; else z=y; return(z); }