Compilare: user.cpp: In function ‘int bellman_ford(const int&)’: user.cpp:24:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0; j < G[i].size (); ++j) ^ user.cpp: In function ‘std::pair<int, int> _binary_search(int, int, const int&)’: user.cpp:54:23: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] middle = left + right >> 1; ^