Compilare: main.cpp: In function 'void bellman(int)': main.cpp:27:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<gg[u].size(); i++) ~^~~~~~~~~~~~~ main.cpp: In function 'void dfs(int, int)': main.cpp:44:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<g[nod].size(); i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:49:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] { freopen("import.in", "r", stdin); ^ main.cpp:50:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("import.out", "w", stdout); ^ main.cpp:52:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &n, &m, &k); ^ main.cpp:54:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ main.cpp:59:47: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &x, &y, &cost, &tip); ^