Compilare: user.cpp: In function ‘void dijkstra(int)’: user.cpp:56:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[nod].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:78:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("gravity.in", "r", stdin); ^ user.cpp:79:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("gravity.out", "w", stdout); ^ user.cpp:81:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:83:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", s[i]+1); ^