Compilare: user.cpp: In function ‘int nr_cuv(int, int)’: user.cpp:20:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(isalpha(s[lit]) && lit<s.size() && lit<p2){ ^ user.cpp:22:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(lit<p2 && lit<s.size() && isalpha(s[lit])) ^ user.cpp:25:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(lit<p2 && lit<s.size() && !isalpha(s[lit])){ ^ user.cpp:26:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(lit<p2 && lit<s.size() && !isalpha(s[lit])) ^ user.cpp: In function ‘int main()’: user.cpp:39:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<s.size();++i) ^ user.cpp:41:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(!isalpha(s[i]) && i<s.size()) ^ user.cpp:35:6: warning: unused variable ‘i’ [-Wunused-variable] int i=0,st=0,fraze=0; ^