answer.code: In function ‘int main()’:
answer.code:318:26: warning: narrowing conversion of ‘i’ from ‘int’ to ‘double’ [-Wnarrowing]
  318 |             a.push_back({i, j});
      |                          ^
answer.code:318:29: warning: narrowing conversion of ‘j’ from ‘int’ to ‘double’ [-Wnarrowing]
  318 |             a.push_back({i, j});
      |                             ^
answer.code:350:12: error: redeclaration of ‘double ans’
  350 |     double ans = 1E18;
      |            ^~~
answer.code:322:12: note: ‘double ans’ previously declared here
  322 |     double ans = 1E18;
      |            ^~~