Răspuns:
#include <iostream>
#include <cstring>
using namespace std;
int main(){
char s[31];
cin.get(s,31);
cin.get();
int ok=0;
for(int i=0;i<strlen(s);++i){
if(s[i]>='A' && s[i]<='Z' || s[i]>='a' && s[i]<='z' || s[i]==' '){
;
}else ok++;
}
if(ok==0)
cout<<"DA";
else cout<<"NU";
return 0;
}
Explicație: