Compilare: user.cpp: In function ‘void Dijkstra()’: user.cpp:75:52: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < V[ node_curr ].size(); i += 2) { ^ user.cpp: In function ‘void readData()’: user.cpp:42:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(FIN, "r", stdin); ^ user.cpp:44:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &nodes, &edges); ^ user.cpp:48:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &x, &y, &cost); ^ user.cpp: In function ‘void writeData()’: user.cpp:99:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(FOUT, "w", stdout); ^