Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:15:9: warning: unused variable ‘ans’ [-Wunused-variable] int ans, i, j, l, r, num = 0; ^ user.cpp:15:17: warning: unused variable ‘j’ [-Wunused-variable] int ans, i, j, l, r, num = 0; ^ user.cpp:15:20: warning: unused variable ‘l’ [-Wunused-variable] int ans, i, j, l, r, num = 0; ^ user.cpp:15:23: warning: unused variable ‘r’ [-Wunused-variable] int ans, i, j, l, r, num = 0; ^ user.cpp: In function ‘int main()’: user.cpp:77:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("karb2.in", "r", stdin); ^ user.cpp:78:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("karb2.out", "w", stdout); ^ user.cpp:80:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &n, &k); ^ user.cpp:82:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &x); ^ user.cpp:86:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &x, &y); ^