Compilare: user.cpp: In function ‘int main()’: user.cpp:11:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<=strlen(s);i++) ^ user.cpp:13:21: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if(s[i]<='Z'&&s[i]>='A'||s[i]<='z'&&s[i]>='a') ^