#include<iostream>using namespace std;int main()...{ int c; c=(char)'a'; char* str=isalnum(c)? "yes":"no"; cout<<str<<endl; c='7'; str=isalnum(c)? "yes":"no"; cout<<str<<endl; c='@'; str=isalnum(c)? "yes":"no"; cout<<str<<endl; c='s'; str=isalpha(c)?"yes":"no"; cout<<str<<endl; getchar(); return 0;}