oj.uz

답안 #245326

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
245326 2020-07-06T04:03:11 Z neihcr7j Boat (APIO16_boat) C++14
36 / 100
 455 ms 2644 KB 
#include<bits/stdc++.h>

#define M 1000000007
#define maxn 502

using namespace std;
typedef long long ll;

inline ll norm(ll a) {
  return (a < 0 ? a + M : (a >= M ? a - M : a));
}

inline ll mul(ll a, ll b) {
  return a * b % M;
}

ll power(ll a, ll b) {
  if (b == 0) return 1;
  if (b&1) return mul(power(a, b - 1), a);
  ll t = power(a, b / 2);
  return mul(t, t);
}

ll gt[maxn * 2], igt[maxn * 2];

void precalc(){
  int n = 1000;

  gt[0] = 1;
  for (int i = 1; i <= n; ++i)
    gt[i] = mul(gt[i - 1], i);

  igt[n] = power(gt[n], M - 2);

  for (int i = n - 1; i >= 0; --i)
    igt[i] = mul(igt[i + 1], i + 1);
}

ll C(int n, int k) {
  return mul(mul(gt[n], igt[k]), igt[n - k]);
}


int n;

int l[maxn], r[maxn];
vector < pair < int, int > > seg;
vector < vector < int > > a;
vector < int > leng;

ll dp[maxn * 4][maxn];

int main(){
  #define TASK "ABC"
//  freopen(TASK".inp", "r", stdin); freopen(TASK".out", "w", stdout);
  ios_base::sync_with_stdio(0);

  precalc();

  cin >> n;

  vector < int > ret;

  for (int i = 1; i <= n; ++i) {
    cin >> l[i] >> r[i];

    ret.push_back(l[i]);
    ret.push_back(r[i]);
  }

  sort(ret.begin(), ret.end());

  seg.push_back({ret[0], ret[0]});

  for (int i = 1; i < ret.size(); ++i)
    if (ret[i] != ret[i - 1]) {
    //  if (i == ret.size() || ret[i] != ret[i + 1]) {
    //    seg.push_back({ret[i - 1] + 1, ret[i]});
    //    continue;
    //  }

      if (ret[i - 1] + 1 != ret[i])
        seg.push_back({ret[i - 1] + 1, ret[i] - 1});
      seg.push_back({ret[i], ret[i]});
    }

  a = vector < vector < int > >(seg.size(), vector < int >(0, 0));
  leng = vector < int > (seg.size(), 0);

  for (int i = 0; i < seg.size(); ++i) {
    for (int j = 1; j <= n; ++j)
      if (l[j] <= seg[i].first && seg[i].second <= r[j])
        a[i].push_back(j);
    leng[i] = seg[i].second - seg[i].first + 1;
  }

  ll ans = 0;

  if (seg.size() > 1500) exit(-1);

  for (int i = 0; i < seg.size(); ++i) {
    ll l = leng[i];

    vector < ll > c(a[i].size() + 1, 0), val(a[i].size() + 1, 0);

    c[0] = 1;

    for (int k = 1; k <= a[i].size(); ++k) {
      if (k <= l)
        c[k] = mul(mul(c[k - 1], l - k + 1), power(k, M - 2));

      for (int x = k; x > 0; --x)
        if (x <= l)
          val[k] = norm(val[k] + mul(c[x], C(k - 1, x - 1)));
    }

     int index = 0;

    for (int k = 0; k <= n; ++k) {
      ll res = (k == 0 ? 1 : 0);

      for (int j = 0; j < i; ++j)
        res = norm(res + dp[j][k]);

      while (index < a[i].size() && a[i][index] <= k)
        index++;

      for (int j = index; j < a[i].size(); ++j)
        dp[i][a[i][j]] = norm(dp[i][a[i][j]] + mul(res, val[j - index + 1]));

      ans = norm(ans + dp[i][k]);
    }
  }

  cout << ans;

  return 0;
}

Compilation message

boat.cpp: In function 'int main()':
boat.cpp:75:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 1; i < ret.size(); ++i)
                   ~~^~~~~~~~~~~~
boat.cpp:90:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 0; i < seg.size(); ++i) {
                   ~~^~~~~~~~~~~~
boat.cpp:101:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 0; i < seg.size(); ++i) {
                   ~~^~~~~~~~~~~~
boat.cpp:108:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int k = 1; k <= a[i].size(); ++k) {
                     ~~^~~~~~~~~~~~~~
boat.cpp:125:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
       while (index < a[i].size() && a[i][index] <= k)
              ~~~~~~^~~~~~~~~~~~~
boat.cpp:128:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
       for (int j = index; j < a[i].size(); ++j)
                           ~~^~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# 결과 실행 시간 메모리 Grader output
1 Correct 426 ms 2552 KB Output is correct
2 Correct 433 ms 2424 KB Output is correct
3 Correct 441 ms 2424 KB Output is correct
4 Correct 440 ms 2644 KB Output is correct
5 Correct 429 ms 2424 KB Output is correct
6 Correct 427 ms 2552 KB Output is correct
7 Correct 425 ms 2424 KB Output is correct
8 Correct 429 ms 2428 KB Output is correct
9 Correct 443 ms 2424 KB Output is correct
10 Correct 440 ms 2488 KB Output is correct
11 Correct 435 ms 2424 KB Output is correct
12 Correct 440 ms 2424 KB Output is correct
13 Correct 455 ms 2424 KB Output is correct
14 Correct 431 ms 2424 KB Output is correct
15 Correct 447 ms 2424 KB Output is correct
16 Correct 19 ms 896 KB Output is correct
17 Correct 21 ms 896 KB Output is correct
18 Correct 20 ms 896 KB Output is correct
19 Correct 22 ms 1024 KB Output is correct
20 Correct 20 ms 896 KB Output is correct

Subtask #2
0 / 22.0

# 결과 실행 시간 메모리 Grader output
1 Correct 426 ms 2552 KB Output is correct
2 Correct 433 ms 2424 KB Output is correct
3 Correct 441 ms 2424 KB Output is correct
4 Correct 440 ms 2644 KB Output is correct
5 Correct 429 ms 2424 KB Output is correct
6 Correct 427 ms 2552 KB Output is correct
7 Correct 425 ms 2424 KB Output is correct
8 Correct 429 ms 2428 KB Output is correct
9 Correct 443 ms 2424 KB Output is correct
10 Correct 440 ms 2488 KB Output is correct
11 Correct 435 ms 2424 KB Output is correct
12 Correct 440 ms 2424 KB Output is correct
13 Correct 455 ms 2424 KB Output is correct
14 Correct 431 ms 2424 KB Output is correct
15 Correct 447 ms 2424 KB Output is correct
16 Correct 19 ms 896 KB Output is correct
17 Correct 21 ms 896 KB Output is correct
18 Correct 20 ms 896 KB Output is correct
19 Correct 22 ms 1024 KB Output is correct
20 Correct 20 ms 896 KB Output is correct
21 Runtime error 10 ms 1920 KB Execution failed because the return code was nonzero
22 Halted 0 ms 0 KB -

Subtask #3
27.0 / 27.0

# 결과 실행 시간 메모리 Grader output
1 Correct 26 ms 2040 KB Output is correct
2 Correct 25 ms 2036 KB Output is correct
3 Correct 25 ms 2048 KB Output is correct
4 Correct 26 ms 2040 KB Output is correct
5 Correct 27 ms 2048 KB Output is correct
6 Correct 31 ms 2048 KB Output is correct
7 Correct 33 ms 2040 KB Output is correct
8 Correct 30 ms 2040 KB Output is correct
9 Correct 30 ms 2040 KB Output is correct
10 Correct 31 ms 2048 KB Output is correct
11 Correct 26 ms 2048 KB Output is correct
12 Correct 25 ms 2048 KB Output is correct
13 Correct 25 ms 2048 KB Output is correct
14 Correct 25 ms 2048 KB Output is correct
15 Correct 26 ms 2048 KB Output is correct
16 Correct 11 ms 1152 KB Output is correct
17 Correct 10 ms 1024 KB Output is correct
18 Correct 10 ms 1024 KB Output is correct
19 Correct 10 ms 1024 KB Output is correct
20 Correct 12 ms 1152 KB Output is correct

Subtask #4
0 / 42.0

# 결과 실행 시간 메모리 Grader output
1 Correct 426 ms 2552 KB Output is correct
2 Correct 433 ms 2424 KB Output is correct
3 Correct 441 ms 2424 KB Output is correct
4 Correct 440 ms 2644 KB Output is correct
5 Correct 429 ms 2424 KB Output is correct
6 Correct 427 ms 2552 KB Output is correct
7 Correct 425 ms 2424 KB Output is correct
8 Correct 429 ms 2428 KB Output is correct
9 Correct 443 ms 2424 KB Output is correct
10 Correct 440 ms 2488 KB Output is correct
11 Correct 435 ms 2424 KB Output is correct
12 Correct 440 ms 2424 KB Output is correct
13 Correct 455 ms 2424 KB Output is correct
14 Correct 431 ms 2424 KB Output is correct
15 Correct 447 ms 2424 KB Output is correct
16 Correct 19 ms 896 KB Output is correct
17 Correct 21 ms 896 KB Output is correct
18 Correct 20 ms 896 KB Output is correct
19 Correct 22 ms 1024 KB Output is correct
20 Correct 20 ms 896 KB Output is correct
21 Runtime error 10 ms 1920 KB Execution failed because the return code was nonzero
22 Halted 0 ms 0 KB -