Compilare: user.cpp: In function ‘int main()’: user.cpp:6:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] { freopen("inter.in", "r",stdin); ^ user.cpp:7:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("inter.out", "w",stdout); ^ user.cpp:9:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:13:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ user.cpp:22:9: warning: ‘jj’ may be used uninitialized in this function [-Wmaybe-uninitialized] if(j+1==jj){ ^ user.cpp:22:13: warning: ‘j’ may be used uninitialized in this function [-Wmaybe-uninitialized] if(j+1==jj){ ^