Submission #995386

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Source Code Expand

#include <bits/stdc++.h>
#define int long long
#define range(i,x,y) i=(x);i<(y);i++
#define rep(i,n) for(int i=0,i##_len=n;i<i##_len;i++)
#define all(x) begin(x),end(x)
#define lim(x,r,l) (r<=x&&x<l)
typedef long long ll;
typedef long double ld;
using namespace std;

int t(int x, const vector<int>& starts, const vector<int>& spans, int fix){
  auto itr =  lower_bound(spans.begin(), spans.begin() + fix, x);
  int k = itr - spans.begin();
  return (x / (k + 1)) + starts[k];
}
signed main(){
  int n, a; cin >> n >> a;
  vector<int> d{0,2+a,3+a,4+a};
  int k = 1;
  for(int i = 1; i <= n; i++){
    vector<int> mt(d.size());
    rep(j, mt.size()){
      mt[j] = d[j] + (i + k + j - 1) / (k + j);
    }
    int r = n+1; for(auto t: mt){
      r = min(t, r);
    }
    if(mt.size() <= 1 || mt.back() <= *(mt.end() - 2)){
      d.push_back(r + a + 1);
    }
    if(mt[0] >= mt[1]){
      d.erase(d.begin());
      k++;
    }
    if(i == n){
      cout << r << endl;
    }
  }
}

Submission Info

Judge Result