Compilare: main.cpp: In function 'int main()': main.cpp:50:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i + k - 1 < stk.size(); ++i) { ~~~~~~~~~~^~~~~~~~~~~~ main.cpp:34:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("drept.in", "r", stdin); ^ main.cpp:35:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("drept.out", "w", stdout); ^ main.cpp:38:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d\n", &n, &k); ^ main.cpp:40:50: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d\n", &points[i].x, &points[i].y); ^