View Compilation Error

0_0_38796769_31637.cpp: In function 'LL inv2(const LL&)':
0_0_38796769_31637.cpp:22:27: error: 'inv' was not declared in this scope; did you mean 'inv2'?
   22 |     return i<=1?1:(P-P/i)*inv(P%i)%P;
      |                           ^~~
      |                           inv2