oj.uz

Submission #259154

# Submission time Handle Problem Language Result Execution time Memory
259154 2020-08-07T09:02:33 Z KoD Beads and wires (APIO14_beads) C++17
100 / 100
 284 ms 28396 KB 
#line 1 "main.cpp"

/**
 * @title Template
 */

#include <iostream>
#include <algorithm>
#include <utility>
#include <numeric>
#include <vector>
#include <array>
#include <tuple>
#include <cassert>
#include <random>

#line 2 "/Users/kodamankod/Desktop/Programming/Library/other/chmin_chmax.cpp"

template <class T, class U>
constexpr bool chmin(T &lhs, const U &rhs) {
  if (lhs > rhs) { 
    lhs = rhs; 
    return true; 
  }
  return false;
}

template <class T, class U>
constexpr bool chmax(T &lhs, const U &rhs) {
  if (lhs < rhs) { 
    lhs = rhs; 
    return true; 
  }
  return false;
}

/**
 * @title Chmin/Chmax
 */
#line 2 "/Users/kodamankod/Desktop/Programming/Library/other/range.cpp"

#line 4 "/Users/kodamankod/Desktop/Programming/Library/other/range.cpp"

class range {
public:
  class iterator {
  private:
    int64_t M_position;

  public:
    constexpr iterator(int64_t position) noexcept: M_position(position) { }
    constexpr void operator ++ () noexcept { ++M_position; }
    constexpr bool operator != (iterator other) const noexcept { return M_position != other.M_position; }
    constexpr int64_t operator * () const noexcept { return M_position; }

  };

  class reverse_iterator {
  private:
    int64_t M_position;
  
  public:
    constexpr reverse_iterator(int64_t position) noexcept: M_position(position) { }
    constexpr void operator ++ () noexcept { --M_position; }
    constexpr bool operator != (reverse_iterator other) const noexcept { return M_position != other.M_position; }
    constexpr int64_t operator * () const noexcept { return M_position; }

  };
  
private:
  const iterator M_first, M_last;

public:
  constexpr range(int64_t first, int64_t last) noexcept: M_first(first), M_last(std::max(first, last)) { }
  constexpr iterator begin() const noexcept { return M_first; }
  constexpr iterator end() const noexcept { return M_last; }
  constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(*M_last - 1); } 
  constexpr reverse_iterator rend() const noexcept { return reverse_iterator(*M_first - 1); } 

};

/**
 * @title Range
 */
#line 2 "/Users/kodamankod/Desktop/Programming/Library/other/rev.cpp"

#include <type_traits>
#include <iterator>
#line 6 "/Users/kodamankod/Desktop/Programming/Library/other/rev.cpp"

template <class T>
class rev_impl {
public:
  using iterator = typename std::decay<T>::type::reverse_iterator;

private:
  const iterator M_begin;
  const iterator M_end;

public:
  constexpr rev_impl(T &&cont) noexcept: M_begin(std::rbegin(cont)), M_end(std::rend(cont)) { }
  constexpr iterator begin() const noexcept { return M_begin; }
  constexpr iterator end() const noexcept { return M_end; }

};

template <class T>
constexpr decltype(auto) rev(T &&cont) {
  return rev_impl<T>(std::forward<T>(cont));
}

/**
 * @title Reverser
 */
#line 19 "main.cpp"

using i32 = int32_t;
using i64 = int64_t;
using u32 = uint32_t;
using u64 = uint64_t;

constexpr i32 inf32 = (i32(1) << 30) - 1;
constexpr i64 inf64 = (i64(1) << 62) - 1;

struct edge_t {
  i32 to, cost;
  edge_t(i32 t, i32 c): to(t), cost(c) { }
};

i32 N, ans;
std::vector<edge_t> graph[200000];
i32 root[200000], max_c[200000];

void dfs(i32 u, i32 p) {
  root[u] = 0;
  max_c[u] = -inf32;
  for (auto [v, c]: graph[u]) {
    if (v == p) continue;
    dfs(v, u);
    i32 tmp = std::max(root[v], root[v] + max_c[v] + c);
    root[u] += tmp;
    chmax(max_c[u], root[v] + c - tmp);
  }
}

void push(i32 u, i32 p, i32 rt, i32 mc) {
  root[u] = 0;
  max_c[u] = -inf32;
  for (auto [v, c]: graph[u]) {
    if (v == p) {
      root[v] = rt;
      max_c[v] = mc;
    }
    i32 tmp = std::max(root[v], root[v] + max_c[v] + c);
    root[u] += tmp;
    chmax(max_c[u], root[v] + c - tmp);
  }
  chmax(ans, root[u]);
  i32 size = graph[u].size();
  std::vector<i32> rt_pref(size + 1), mc_pref(size + 1, -inf32);
  {
    i32 idx = 0;
    for (auto [v, c]: graph[u]) {
      ++idx;
      i32 tmp = std::max(root[v], root[v] + max_c[v] + c);
      rt_pref[idx] = rt_pref[idx - 1] + tmp;
      mc_pref[idx] = std::max(mc_pref[idx - 1], root[v] + c - tmp);
    }
  }
  std::vector<i32> rt_suff(size + 1), mc_suff(size + 1, -inf32);
  {
    i32 idx = 0;
    for (auto [v, c]: rev(graph[u])) {
      ++idx;
      i32 tmp = std::max(root[v], root[v] + max_c[v] + c);
      rt_suff[idx] = rt_suff[idx - 1] + tmp;
      mc_suff[idx] = std::max(mc_suff[idx - 1], root[v] + c - tmp);
    }
  }
  for (auto i: range(0, size)) {
    auto [v, c] = graph[u][i];
    if (v != p) {
      push(v, u, rt_pref[i] + rt_suff[size - i - 1], std::max(mc_pref[i], mc_suff[size - i - 1]));
    }
  }
}

int main() {
  std::ios_base::sync_with_stdio(false);
  std::cin.tie(nullptr);
  std::cin >> N;
  for (i32 i = 1; i < N; ++i) {
    i32 u, v, c;
    std::cin >> u >> v >> c;
    --u; --v;
    graph[u].emplace_back(v, c);
    graph[v].emplace_back(u, c);
  }
  dfs(0, -1);
  push(0, -1, 0, -inf32);
  std::cout << ans << '\n';
  return 0;
}

Compilation message

main.cpp: In function 'void push(i32, i32, i32, i32)':
main.cpp:84:15: warning: unused variable 'c' [-Wunused-variable]

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4992 KB Output is correct
2 Correct 4 ms 4992 KB Output is correct
3 Correct 3 ms 5120 KB Output is correct
4 Correct 3 ms 4992 KB Output is correct
5 Correct 3 ms 4992 KB Output is correct
6 Correct 4 ms 4992 KB Output is correct
7 Correct 3 ms 4992 KB Output is correct
8 Correct 4 ms 4992 KB Output is correct
9 Correct 3 ms 4992 KB Output is correct
10 Correct 3 ms 4992 KB Output is correct
11 Correct 3 ms 5120 KB Output is correct
12 Correct 3 ms 4992 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4992 KB Output is correct
2 Correct 4 ms 4992 KB Output is correct
3 Correct 3 ms 5120 KB Output is correct
4 Correct 3 ms 4992 KB Output is correct
5 Correct 3 ms 4992 KB Output is correct
6 Correct 4 ms 4992 KB Output is correct
7 Correct 3 ms 4992 KB Output is correct
8 Correct 4 ms 4992 KB Output is correct
9 Correct 3 ms 4992 KB Output is correct
10 Correct 3 ms 4992 KB Output is correct
11 Correct 3 ms 5120 KB Output is correct
12 Correct 3 ms 4992 KB Output is correct
13 Correct 3 ms 4992 KB Output is correct
14 Correct 3 ms 4992 KB Output is correct
15 Correct 3 ms 4992 KB Output is correct
16 Correct 3 ms 4992 KB Output is correct
17 Correct 3 ms 4992 KB Output is correct
18 Correct 3 ms 4992 KB Output is correct
19 Correct 3 ms 4992 KB Output is correct
20 Correct 3 ms 4992 KB Output is correct
21 Correct 3 ms 4992 KB Output is correct
22 Correct 4 ms 5120 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4992 KB Output is correct
2 Correct 4 ms 4992 KB Output is correct
3 Correct 3 ms 5120 KB Output is correct
4 Correct 3 ms 4992 KB Output is correct
5 Correct 3 ms 4992 KB Output is correct
6 Correct 4 ms 4992 KB Output is correct
7 Correct 3 ms 4992 KB Output is correct
8 Correct 4 ms 4992 KB Output is correct
9 Correct 3 ms 4992 KB Output is correct
10 Correct 3 ms 4992 KB Output is correct
11 Correct 3 ms 5120 KB Output is correct
12 Correct 3 ms 4992 KB Output is correct
13 Correct 3 ms 4992 KB Output is correct
14 Correct 3 ms 4992 KB Output is correct
15 Correct 3 ms 4992 KB Output is correct
16 Correct 3 ms 4992 KB Output is correct
17 Correct 3 ms 4992 KB Output is correct
18 Correct 3 ms 4992 KB Output is correct
19 Correct 3 ms 4992 KB Output is correct
20 Correct 3 ms 4992 KB Output is correct
21 Correct 3 ms 4992 KB Output is correct
22 Correct 4 ms 5120 KB Output is correct
23 Correct 6 ms 5248 KB Output is correct
24 Correct 6 ms 5248 KB Output is correct
25 Correct 6 ms 5248 KB Output is correct
26 Correct 9 ms 5504 KB Output is correct
27 Correct 9 ms 5632 KB Output is correct
28 Correct 8 ms 5888 KB Output is correct
29 Correct 9 ms 5760 KB Output is correct
30 Correct 9 ms 5760 KB Output is correct
31 Correct 11 ms 6528 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4992 KB Output is correct
2 Correct 4 ms 4992 KB Output is correct
3 Correct 3 ms 5120 KB Output is correct
4 Correct 3 ms 4992 KB Output is correct
5 Correct 3 ms 4992 KB Output is correct
6 Correct 4 ms 4992 KB Output is correct
7 Correct 3 ms 4992 KB Output is correct
8 Correct 4 ms 4992 KB Output is correct
9 Correct 3 ms 4992 KB Output is correct
10 Correct 3 ms 4992 KB Output is correct
11 Correct 3 ms 5120 KB Output is correct
12 Correct 3 ms 4992 KB Output is correct
13 Correct 3 ms 4992 KB Output is correct
14 Correct 3 ms 4992 KB Output is correct
15 Correct 3 ms 4992 KB Output is correct
16 Correct 3 ms 4992 KB Output is correct
17 Correct 3 ms 4992 KB Output is correct
18 Correct 3 ms 4992 KB Output is correct
19 Correct 3 ms 4992 KB Output is correct
20 Correct 3 ms 4992 KB Output is correct
21 Correct 3 ms 4992 KB Output is correct
22 Correct 4 ms 5120 KB Output is correct
23 Correct 6 ms 5248 KB Output is correct
24 Correct 6 ms 5248 KB Output is correct
25 Correct 6 ms 5248 KB Output is correct
26 Correct 9 ms 5504 KB Output is correct
27 Correct 9 ms 5632 KB Output is correct
28 Correct 8 ms 5888 KB Output is correct
29 Correct 9 ms 5760 KB Output is correct
30 Correct 9 ms 5760 KB Output is correct
31 Correct 11 ms 6528 KB Output is correct
32 Correct 38 ms 8056 KB Output is correct
33 Correct 40 ms 8056 KB Output is correct
34 Correct 42 ms 8108 KB Output is correct
35 Correct 239 ms 17528 KB Output is correct
36 Correct 284 ms 17656 KB Output is correct
37 Correct 270 ms 17776 KB Output is correct
38 Correct 176 ms 20796 KB Output is correct
39 Correct 171 ms 21080 KB Output is correct
40 Correct 178 ms 20704 KB Output is correct
41 Correct 278 ms 28396 KB Output is correct