Compilare: main.cpp: In function 'int main()': main.cpp:38:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<nr.size();i++){ ~^~~~~~~~~~ main.cpp:67:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<nr.size();i++){ ~^~~~~~~~~~