reverse.cpp: In function 'long long int rev(long long int*, long long int)':
reverse.cpp:3:9: error: 'll' was not declared in this scope
3 | for(ll i=n-1; i>=0; i--)
| ^~
reverse.cpp:3:19: error: 'i' was not declared in this scope
3 | for(ll i=n-1; i>=0; i--)
| ^
reverse.cpp:5:9: error: 'cout' was not declared in this scope
5 | cout<<arr[i]<<' ';
| ^~~~
reverse.cpp:5:15: error: 'arr' was not declared in this scope
5 | cout<<arr[i]<<' ';
| ^~~
reverse.cpp:7:5: error: 'cout' was not declared in this scope
7 | cout<<endl;
| ^~~~
reverse.cpp:7:11: error: 'endl' was not declared in this scope
7 | cout<<endl;
| ^~~~
reverse.cpp:8:1: warning: no return statement in function returning non-void [-Wreturn-type]
8 | }
| ^