Compilare: user.cpp: In function ‘void dijkstra()’: user.cpp:27:13: warning: unused variable ‘COST’ [-Wunused-variable] int COST = q.top().x; ^ user.cpp: In function ‘int main()’: user.cpp:83:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < Sol.size(); ++i) ^ user.cpp:46:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("drum2.in", "r", stdin); ^ user.cpp:47:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("drum2.out", "w", stdout); ^ user.cpp:48:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:55:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[k][i][j]); ^