Compilare: user.cpp: In function ‘bool cmp(int, int, int, int)’: user.cpp:7:29: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] return xa < ya || xa == ya && xb < yb; ^ user.cpp: In function ‘int main()’: user.cpp:16:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("points.in", "r", stdin); ^ user.cpp:17:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("points.out", "w", stdout); ^ user.cpp:19:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &N); ^ user.cpp:22:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^