Compilare: main.cpp: In function 'bool bellman_ford()': main.cpp:44:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < edges[node].size(); i++){ ~~^~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'void read()': main.cpp:18:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &N); ^ main.cpp:21:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a, &b); ^ main.cpp: In function 'int main()': main.cpp:68:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("harta.in", "r", stdin); ^ main.cpp:69:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("harta.out", "w", stdout); ^