Compilare: main.cpp: In function 'std::vector<int> bellman_ford(const std::vector<std::vector<std::pair<int, int> > >&, int)': main.cpp:21:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(visited[current] >= graph.size()) { main.cpp:29:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < graph[current].size(); i++) { ~~^~~~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:61:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i < dist.size(); i++) ~~^~~~~~~~~~~~~ main.cpp:44:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("bellmanford.in", "r", stdin); ^ main.cpp:45:44: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("bellmanford.out", "w", stdout); ^ main.cpp:47:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ main.cpp:52:45: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &src, &dst, &weight); ^