Compilare: user.cpp: In function ‘void solve()’: user.cpp:98:27: warning: unused variable ‘old’ [-Wunused-variable] int i, x, y, ans = 0, old; ^ user.cpp: In function ‘void read()’: user.cpp:31:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &n, &k); ^ user.cpp:33:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &x, &y); ^ user.cpp: In function ‘void solve()’: user.cpp:103:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &x ,&y); ^ user.cpp: In function ‘int main()’: user.cpp:133:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ct.in", "r", stdin); ^ user.cpp:134:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ct.out", "w", stdout); ^ user.cpp:136:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &T); ^