Compilare: main.cpp: In function 'std::vector<int> intersect(std::vector<int>, std::vector<int>)': main.cpp:23:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<a.size() && j<b.size()) ~^~~~~~~~~ main.cpp:23:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<a.size() && j<b.size()) ~^~~~~~~~~ main.cpp: In function 'std::vector<int> reuniune(std::vector<int>, std::vector<int>)': main.cpp:37:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<a.size()&&j<b.size()) ~^~~~~~~~~ main.cpp:37:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<a.size()&&j<b.size()) ~^~~~~~~~~ main.cpp:46:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<a.size()) ~^~~~~~~~~ main.cpp:50:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<b.size()) ~^~~~~~~~~ main.cpp: In function 'int main()': main.cpp:107:24: warning: unused variable 'x' [-Wunused-variable] int first,last,x; ^