#include <bits/stdc++.h>
using namespace std;
long long n, k;
string ans;
void fu(int x) {
  if (x == 0) {
    ans += "()";
    return;
  }
  if (k >= x) {
    ans += "(";
    k -= x;
    fu(x - 1);
    ans += ")";
    return;
  }
  ans += "()";
  fu(x - 1);
}
int main() {
  cin >> n >> k;
  fu(n - 1);
  if (k > 0)
    cout << "Impossible";
  else
    cout << ans;
  cout << endl;
  return 0;
}
