Compilare: main.cpp: In function 'int main()': main.cpp:38:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (p1 < a.size() && a[p1].first < i) ~~~^~~~~~~~~~ main.cpp:40:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (p2 < b.size() && b[p2].first < i) ~~~^~~~~~~~~~ main.cpp:42:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (p1 >= a.size() || b[p2].second > a[p1].second) ~~~^~~~~~~~~~~