Compilare: user.cpp: In function ‘void solve(int, int)’: user.cpp:35:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(v.size() <= k) { ^ user.cpp: In function ‘int main()’: user.cpp:59:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < rasp.size(); ++ i) { ^ user.cpp:50:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("armonica.in", "r", stdin); ^ user.cpp:51:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("armonica.out", "w", stdout); ^ user.cpp:53:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &b); ^