Compilare: main.cpp: In function 'bool isThere(long long unsigned int)': main.cpp:14:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < Map[key].size(); ++i) ~~^~~~~~~~~~~~~~~~~ main.cpp:15:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if ( Map[key][i] == x ) return 1;