Compilare: user.cpp: In function ‘void solve()’: user.cpp:47:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < nodes.size(); i++) { ^ user.cpp: In function ‘void read()’: user.cpp:20:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d ", &n, &m); ^ user.cpp:23:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &cost[i]); ^ user.cpp:30:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d ", &x, &y); ^ user.cpp: In function ‘int main()’: user.cpp:61:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("srevni.in", "r", stdin); ^ user.cpp:62:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("srevni.out", "w", stdout); ^