Compilare: user.cpp: In function ‘void Dijkstra()’: user.cpp:72:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < V[ax][ay].size(); ++ i) ^ user.cpp: In function ‘void read()’: user.cpp:32:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("volum.in", "r", stdin); ^ user.cpp:33:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:37:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i][j]); ^ user.cpp: In function ‘void write()’: user.cpp:107:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("volum.out", "w", stdout); ^