Compilare: user.cpp: In function ‘int solve()’: user.cpp:22:49: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < graph[adj].size(); i++) { ^ user.cpp:35:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:53:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ans.size() - 1; i++) ^ user.cpp:38:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ciclueuler.in", "r", stdin); ^ user.cpp:39:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ciclueuler.out", "w", stdout); ^ user.cpp:40:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:42:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^