Compilare: main.cpp: In function 'void compute_distances(int, int*)': main.cpp:25:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < edges[node].size(); ++i) ~~^~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:70:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < solution.size(); ++i) ~~^~~~~~~~~~~~~~~~~ main.cpp:39:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("graf.in", "r", stdin); ^ main.cpp:40:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("graf.out", "w", stdout); ^