View Compilation Error

0_0_39591142_26431.cpp: In function 'int main()':
0_0_39591142_26431.cpp:16:31: error: 'in' was not declared in this scope; did you mean 'i'?
   16 |         for(int i=1;i<=n;i++) in[i]=0;
      |                               ^~
      |                               i