oj.uz

Submission #697965

# Submission time Handle Problem Language Result Execution time Memory
697965 2023-02-11T15:34:17 Z dattranxxx Building Bridges (CEOI17_building) C++11
100 / 100
 76 ms 65260 KB 
#include<bits/stdc++.h>
using namespace std;
using ll = long long;
 
const int N = 1e5 + 5;
const ll INF = 1e12;
const ll LLINF = 1e18;
ll h[N], w[N];
int n;
 
ll dp[N];
 
ll sqr(ll x) {
  return x * x;
}
 
namespace task1 {
  void solve() {
    dp[1] = 0;
    for (int i = 2; i <= n; ++i) {
      dp[i] = LLINF;
      for (int j = i - 1; j; --j) {
        dp[i] = min(dp[i], dp[j] + sqr(h[i] - h[j]) + (w[i - 1] - w[j]));
      }
    }
    cout << dp[n];
  }
}
 
namespace task2 {
  const int C = 1e6;
  
  struct Line {
    ll a, b;
    Line(ll a = INF, ll b = INF): a(a), b(b) {}
    ll get(ll x) {
      return a * x + b;
    }
  };
  
  struct LichaoTree {
    // vector<Line> cont;
    // void update(ll a, ll b) {
      // cont.emplace_back(a, b);
    // }
//     
    // ll get(ll x) {
      // ll res = INF;
      // for (auto& l : cont)
        // res = min(res, l.get(x));
      // return res;
    // }
    Line v; ll x, res;
    Line lct[(C + 1) * 4];
    void update(int i, int l, int r) {
      int m = (l + r) / 2;
      if (v.a < lct[i].a) swap(v, lct[i]);
      if (v.get(m) < lct[i].get(m)) {
        swap(v, lct[i]);
        if (l != r) update(i * 2 + 1, m + 1, r);
      } else {
        if (l != r) update(i * 2, l, m);
      }
    }
    
    void get(int i, int l, int r) {
      res = min(res, lct[i].get(x));
      if (l == r) return;
      int m = (l + r) / 2;
      if (x <= m) get(i * 2, l, m);
      else get(i * 2 + 1, m + 1, r);
    }
    
    void update(ll a, ll b) {
      v = Line(a, b);
      update(1, 0, C);
    }
    
    ll get(ll x) {
      res = LLINF;
      this->x = x;
      get(1, 0, C);
      return res;
    }
    
  } lct;
  
  void solve() {
    dp[1] = 0;
    lct.update(-2 * h[1], dp[1] + sqr(h[1]) - w[1]);
    for (int i = 2; i <= n; ++i) {
      // dp[i] = h[i]^2 + w[i-1] + MIN[(-2h[j]) * h[i] + dp[j] + h[j]^2 - w[j]]
      dp[i] = sqr(h[i]) + w[i-1] + lct.get(h[i]);
      lct.update(-2 * h[i], dp[i] + sqr(h[i]) - w[i]);
    }
    cout << dp[n];
  }
}
 
 
int main() {
  cin.tie(0)->sync_with_stdio(0); cout.tie(0);
  cin >> n;
  for (int i = 1; i <= n; ++i)
    cin >> h[i];
  for (int i = 1; i <= n; ++i)
    cin >> w[i],
    w[i] += w[i - 1];
    
  if (n <= 1000) task1::solve();
  else task2::solve();
  
	return 0;
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 26 ms 62888 KB Output is correct
2 Correct 29 ms 62924 KB Output is correct
3 Correct 25 ms 62864 KB Output is correct
4 Correct 25 ms 62868 KB Output is correct
5 Correct 29 ms 62928 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 74 ms 65148 KB Output is correct
2 Correct 67 ms 65204 KB Output is correct
3 Correct 66 ms 65152 KB Output is correct
4 Correct 64 ms 65220 KB Output is correct
5 Correct 64 ms 65224 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 26 ms 62888 KB Output is correct
2 Correct 29 ms 62924 KB Output is correct
3 Correct 25 ms 62864 KB Output is correct
4 Correct 25 ms 62868 KB Output is correct
5 Correct 29 ms 62928 KB Output is correct
6 Correct 74 ms 65148 KB Output is correct
7 Correct 67 ms 65204 KB Output is correct
8 Correct 66 ms 65152 KB Output is correct
9 Correct 64 ms 65220 KB Output is correct
10 Correct 64 ms 65224 KB Output is correct
11 Correct 76 ms 65260 KB Output is correct
12 Correct 69 ms 65228 KB Output is correct
13 Correct 60 ms 65208 KB Output is correct
14 Correct 71 ms 65220 KB Output is correct
15 Correct 59 ms 65192 KB Output is correct
16 Correct 61 ms 65228 KB Output is correct
17 Correct 47 ms 65184 KB Output is correct
18 Correct 46 ms 65208 KB Output is correct