Codeforces Round #655 (Div. 2) F

題目連結

​​https://codeforces.com/contest/1372/problem/F​​

題面

題意

思路

參考代碼

#include <bits/stdc++.h>
using namespace std;
#define
#define
const int N = 2e5 + 10;
int ans[N];
P query(int l, int r) {
  printf("? %d %d\n", l, r);
  fflush(stdout);
  int x, f;
  scanf("%d%d", &x, &f);
  return MP(x, f);
}
void solve(int l, int r) {
  if (l <= r) {
    P x = query(l, r);
    int L = r - x.second + 1, R = l + x.second - 1;
    if (L <= R) {
      for (int i = L; i <= R; i++) {
        ans[i] = x.first;
      }
      solve(l, L - 1);
      solve(R + 1, r);
    } else {
      int mid = (l + r) / 2;
      solve(l, mid);
      solve(mid + 1, r);
    }
  }
  return;
}
int main() {
  int n;
  scanf("%d", &n);
  solve(1, n);
  printf("! ");
  for (int i = 1; i <= n; i++) {
    printf("%d ", ans[i]);
  }
  puts("");
  fflush(stdout);
  return 0;
}