Compilare: user.cpp: In function ‘int main()’: user.cpp:21:69: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(!st.empty() && s[i]>st.top() && n-i + st.size()>=m) ^ user.cpp:26:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(st.size()<=m) ^ user.cpp:14:9: warning: unused variable ‘nr’ [-Wunused-variable] int nr=0; ^