oj.uz

Submission #977359

# Submission time Handle Problem Language Result Execution time Memory
977359 2024-05-07T19:21:45 Z duckindog Building Bridges (CEOI17_building) C++17
60 / 100
 67 ms 9212 KB 
#include <bits/stdc++.h>

using namespace std;

const int N = 100'000 + 10;
int n;
int h[N], w[N];
int d[N];

struct Line { 
  long long a, b;

  Line() : a(0), b(1'000'000'000'000) {}
  Line(long long a, long long b) : a(a), b(b) {}

  double x(const auto& rhs) { return 1.0 * (b - rhs.b) / (rhs.a - a); }
  long long cal(long long x) { return a * x + b; }
} f[N << 2];
vector<int> rrh;

void insert(int s, int l, int r, Line line) { 
  if (l == r) { 
    // if (f[s].cal(l - 1) > line.cal(l - 1)) f[s] = line;
    f[s] = line;
    return;
  }
  int mid = l + r >> 1;
  if (f[s].a > line.a) swap(f[s], line);
  if (f[s].cal(rrh[mid - 1]) <= line.cal(rrh[mid - 1])) insert(s << 1, l, mid, line);
  else { 
    swap(f[s], line);
    insert(s << 1 | 1, mid + 1, r, line);
  }
}

long long query(int s, int l, int r, int i) { 
  if (i < l || i > r) return 1'000'000'000'000'000;
  if (l == r) return f[s].cal(rrh[i - 1]);
  int mid = l + r >> 1;
  if (i <= mid) return min(f[s].cal(rrh[i - 1]), query(s << 1, l, mid, i));
  return min(f[s].cal(rrh[i - 1]), query(s << 1 | 1, mid + 1, r, i));
}

long long dp[N];

int32_t main() { 
  cin.tie(0)->sync_with_stdio(0);

  cin >> n;
  for (int i = 1; i <= n; ++i) cin >> h[i];
  for (int i = 1; i <= n; ++i) cin >> w[i];

  for (int i = 1; i <= n; ++i) d[i] = d[i - 1] + w[i];

  rrh = vector<int>(h + 1, h + n + 1);
  sort(rrh.begin(), rrh.end());
  rrh.resize(unique(rrh.begin(), rrh.end()) - rrh.begin());

  insert(1, 1, rrh.size(), {-2 * h[1], 1ll * h[1] * h[1] - d[1]});
  
  for (int i = 2; i <= n; ++i) { 
    int it = lower_bound(rrh.begin(), rrh.end(), h[i]) - rrh.begin() + 1;
    dp[i] = query(1, 1, rrh.size(), it) + 1ll * h[i] * h[i] + d[i - 1];
    insert(1, 1, rrh.size(), {-2 * h[i], 1ll * h[i] * h[i] - d[i] + dp[i]});
  }

  cout << dp[n] << "\n";
}

Compilation message

building.cpp:16:18: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   16 |   double x(const auto& rhs) { return 1.0 * (b - rhs.b) / (rhs.a - a); }
      |                  ^~~~
building.cpp: In function 'void insert(int, int, int, Line)':
building.cpp:27:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   27 |   int mid = l + r >> 1;
      |             ~~^~~
building.cpp: In function 'long long int query(int, int, int, int)':
building.cpp:39:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   39 |   int mid = l + r >> 1;
      |             ~~^~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7256 KB Output is correct
2 Correct 4 ms 7260 KB Output is correct
3 Correct 2 ms 7256 KB Output is correct
4 Correct 2 ms 7256 KB Output is correct
5 Correct 2 ms 7260 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 46 ms 8940 KB Output is correct
2 Correct 61 ms 9044 KB Output is correct
3 Correct 46 ms 9044 KB Output is correct
4 Correct 41 ms 9048 KB Output is correct
5 Correct 35 ms 9048 KB Output is correct

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 7256 KB Output is correct
2 Correct 4 ms 7260 KB Output is correct
3 Correct 2 ms 7256 KB Output is correct
4 Correct 2 ms 7256 KB Output is correct
5 Correct 2 ms 7260 KB Output is correct
6 Correct 46 ms 8940 KB Output is correct
7 Correct 61 ms 9044 KB Output is correct
8 Correct 46 ms 9044 KB Output is correct
9 Correct 41 ms 9048 KB Output is correct
10 Correct 35 ms 9048 KB Output is correct
11 Correct 58 ms 9052 KB Output is correct
12 Correct 67 ms 8896 KB Output is correct
13 Correct 39 ms 9052 KB Output is correct
14 Correct 57 ms 9052 KB Output is correct
15 Correct 48 ms 9052 KB Output is correct
16 Correct 44 ms 9044 KB Output is correct
17 Incorrect 16 ms 9212 KB Output isn't correct
18 Halted 0 ms 0 KB -