Compilare: user.cpp: In function ‘int main()’: user.cpp:22:9: warning: unused variable ‘ans’ [-Wunused-variable] int ans,i,j,k,n,m,l1,c1,l2,c2,inc,sf; ^ user.cpp:19:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rege.in","r",stdin); ^ user.cpp:20:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rege.out","w",stdout); ^ user.cpp:23:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:24:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&l1,&c1); ^ user.cpp:25:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&l2,&c2); ^