Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:16:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < a[x].size(); i++) ~~^~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:21:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("berarii2.in", "r", stdin); ^ user.cpp:22:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("berarii2.out", "w", stdout); ^ user.cpp:24:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i %i", &n, &m, &p); ^ user.cpp:27:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i", &x, &y); ^ user.cpp:32:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &x); ^