Functiile strlwr şi struwr !

#include <iostream>
#include<string.h>
#include <stdio.h>
using namespace std;
int main()
{
 char s1[100],s2[100];
cout<<"tasteaza o fraza: ";
cin.get(s1,100);
cin.get();
cout<<"tasteaza o fraza: ";
cin.get(s2,100);
cin.get();
cout<<strupr(s1)<<endl<<strlwr(s2);
 return 0;
}