Compilare: user.cpp: In function ‘int main()’: user.cpp:17:18: warning: unused variable ‘j’ [-Wunused-variable] int n, m, i, j, x, y, c; ^ user.cpp:14:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "arbint.in", "r", stdin ); ^ user.cpp:15:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "arbint.out", "w", stdout ); ^ user.cpp:19:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%d%d",&n,&m ); ^ user.cpp:21:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%d",&x ); ^ user.cpp:27:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%d%d%d",&c,&x,&y ); ^