View Compilation Error

0_0_39628530_30647.cpp: In function 'long long int read()':
0_0_39628530_30647.cpp:16:16: error: 'getchar_unlocked' was not declared in this scope; did you mean '_getchar_nolock'?
   16 |         char c=getchar_unlocked();
      |                ^~~~~~~~~~~~~~~~
      |                _getchar_nolock