Compilare: main.cpp: In function 'void solve()': main.cpp:32:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(max_heap.size() > half) ~~~~~~~~~~~~~~~~^~~~~~ main.cpp:56:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(max_heap.size() < half) ~~~~~~~~~~~~~~~~^~~~~~ main.cpp:67:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(max_heap.size() > half) ~~~~~~~~~~~~~~~~^~~~~~ main.cpp: At global scope: main.cpp:102:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] main() ^