Compilare: user.cpp: In function ‘void dijkstra(const int&)’: user.cpp:28:12: warning: variable ‘cost’ set but not used [-Wunused-but-set-variable] int x, cost, y, z; ^ user.cpp: In function ‘int main()’: user.cpp:92:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("dbz.in", "r", stdin); ^ user.cpp:93:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("dbz.out", "w", stdout); ^ user.cpp:95:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &n, &m); ^ user.cpp:97:37: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d", &x, &y, &z); ^