Compilare: user.cpp: In function ‘void dijkstra()’: user.cpp:51:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<G[x].size();i++) ^ user.cpp: In function ‘void citire()’: user.cpp:27:34: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(b,sizeof(char),l,stdin); ^ user.cpp: In function ‘int main()’: user.cpp:64:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("dijkstra.in","r",stdin); ^ user.cpp:65:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("dijkstra.out","w",stdout); ^