answer.code: In function ‘int main()’:
answer.code:100:32: error: a function-definition is not allowed here before ‘{’ token
  100 | int fpow(int a, int b, int mod){
      |                                ^
answer.code:107:20: error: a function-definition is not allowed here before ‘{’ token
  107 | int cmp(ii a, ii b){
      |                    ^
answer.code:111:9: warning: empty parentheses were disambiguated as a function declaration [-Wvexing-parse]
  111 | int main(){FIN;
      |         ^~
answer.code:111:9: note: remove parentheses to default-initialize a variable
  111 | int main(){FIN;
      |         ^~
      |         --
answer.code:111:9: note: or replace parentheses with braces to value-initialize a variable
answer.code:111:11: error: a function-definition is not allowed here before ‘{’ token
  111 | int main(){FIN;
      |           ^