Compilare: user.cpp: In function ‘void input()’: user.cpp:13:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:15:51: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] int x, y, z; scanf("%d %d %d", &x, &y, &z); ^ user.cpp: In function ‘int main()’: user.cpp:46:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dijkstra.in","r",stdin); ^ user.cpp:47:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dijkstra.out","w",stdout); ^