#include<stdio.h>
char wap(char words1,char words2);
main()
{
    int i;
    char c[]="China";
    char put[4];
    for(i=0,i<=4,i++){
        wap(c[i],put[i]);
    }
    printf("%s\n",put[4]);
    char wap(char words1,char words2)
    {
        words2=words1+4;
        return words2;
    }
}
编译器说wap函数定义是非法的，请版主指导指导

我自己改了改你再给检查检查
#include<stdio.h>
char wap(char words1,char words2);
main()
{
    int i;
    char c[]="China";
    char put[5];
    for(i=0;i<=4;i++){
        wap(c[i],put[i]);
    }
    printf("%s\n",put[5]);

}
    char wap(char words1,char words2)
    {
        words2=words1+4;
        return words2;
    }