Compilare: main.cpp: In function 'int main()': main.cpp:42:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (sol.size() < n - 1) { ~~~~~~~~~~~^~~~~~~ main.cpp:28:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("mesaj4.in", "r", stdin); ^ main.cpp:29:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("mesaj4.out", "w", stdout); ^ main.cpp:31:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ main.cpp:35:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^