View Compilation Error

0_0_39454462_24372.cpp: In function 'int main()':
0_0_39454462_24372.cpp:236:9: error: 'i' was not declared in this scope
  236 |     rep(i,1,n)
      |         ^
0_0_39454462_24372.cpp:236:5: error: 'rep' was not declared in this scope; did you mean 'frexp'?
  236 |     rep(i,1,n)
      |     ^~~
      |     frexp
0_0_39454462_24372.cpp:321:23: error: 'c' cannot be used as a function
  321 |             ans += ((c(n, k) - c(n - i, k)+mod1)%mod1) * a[i];
      |                      ~^~~~~~
0_0_39454462_24372.cpp:321:33: error: 'c' cannot be used as a function
  321 |             ans += ((c(n, k) - c(n - i, k)+mod1)%mod1) * a[i];
      |                                ~^~~~~~~~~~