Compilare: user.cpp: In function ‘int main()’: user.cpp:37:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i<Not.size(); ++i) ^ user.cpp:25:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("iepuri2.in" , "r", stdin); ^ user.cpp:26:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("iepuri2.out" , "w", stdout); ^ user.cpp:27:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n", &n, &k); ^ user.cpp:31:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^ user.cpp:35:9: warning: ‘root’ may be used uninitialized in this function [-Wmaybe-uninitialized] int root; ^