Compilare: main.cpp: In function 'long double Area(std::vector<Point>)': main.cpp:76:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < vec.size(); ++i) ~~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:96:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < a.size(); ++i){ ~~^~~~~~~~~~ main.cpp:100:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < b.size(); ++j){ ~~^~~~~~~~~~