View Compilation Error

0_0_39080824_6676.cpp: In function 'int main()':
0_0_39080824_6676.cpp:81:39: error: 'inv' was not declared in this scope; did you mean 'Inv'?
   81 |                     prod_p = prod_p * inv(np[posl]) % P;
      |                                       ^~~
      |                                       Inv