Compilare: main.cpp: In function 'bool fa_o_pereche(int)': main.cpp:18:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v1[x].size();i++) ~^~~~~~~~~~~~~ main.cpp:28:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v1[x].size();i++) ~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:54:10: warning: variable 'sem' set but not used [-Wunused-but-set-variable] bool sem= false; ^~~