Compilare: user.cpp: In function ‘int main()’: user.cpp:12:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(s);i++) ^ user.cpp:13:21: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if(s[i]>=65 && s[i]<=90 || s[i]>=97 && s[i]<=122) ^ user.cpp:16:28: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] while(s[i]>=65 && s[i]<=90 || s[i]>=97 && s[i]<=122) ^