func_code_string: #include <bits/stdc++.h>   using namespace std;   int n;   int ans[100000 + 1];   void reverseAns(int l, int r) {     if (l > r) return;     int mid = (l + r) >> 1;     for (int i = 1; i <= mid - l + 1; ++i) {       swap(ans[i + l - 1], ans[r - i + 1]);     }   }   int main() {     ios::sync_with_stdio(false);     cin >> n;     for (int i = 1; i <= n; ++i) {       ans[i] = i;     }     int block = round(sqrt(n));     int tot = n / block;     for (int i = 1; i <= tot; ++i) {       reverseAns((i - 1) * block + 1, i * block);     }     reverseAns(tot * block + 1, n);     for (int i = 1; i <= n; ++i) {       cout << ans[i] <<    ;     }     cout << endl;     return 0;   }   