Compilare: user.cpp: In function ‘bool dijkstra()’: user.cpp:45:13: warning: unused variable ‘cost’ [-Wunused-variable] int cost=X.first; ^ user.cpp: In function ‘int main()’: user.cpp:89:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.in","r",stdin); ^ user.cpp:90:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.out","w",stdout); ^ user.cpp:91:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&n,&m,&s,&d); ^ user.cpp:94:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&x,&y,&ca,&co); ^