Submission #231289

# Submission time Handle Problem Language Result Execution time Memory
231289 2020-05-13T10:11:07 Z AlexLuchianov Boat (APIO16_boat) C++14
27 / 100
2000 ms 3456 KB
#include <iostream>
#include <vector>
#include <algorithm>
#include <cassert>
#include <cmath>
#include <map>

using namespace std;

using ll = long long;
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#define MAX(a, b) (((a) < (b)) ? (b) : (a))

int const nmax = 500;
int const modulo = 1000000007;

class ModuloRing{
private:
  void gcd(int a, int b, int &x, int &y){
    if(b == 0){
      x = 1;
      y = 0;
    } else {
      gcd(b, a % b, x, y);
      int aux = x;
      x = y;
      y = aux - a / b * y;
    }
  }
public:
  int number;
  ModuloRing(ll number_ = 0){
    number = number_ % modulo;
  }
  ModuloRing operator + (ModuloRing a) {
    return {number + a.number};
  }
  ModuloRing operator - (ModuloRing a) {
    return {modulo + number - a.number};
  }
  ModuloRing operator * (ModuloRing a) {
    return {1LL * number * a.number};
  }
  ModuloRing operator / (ModuloRing a) {
    int x, y;
    gcd(a.number, modulo, x, y);
    x %= modulo;
    if(x < 0)
      x += modulo;
    return 1LL * number * x;
  }
};

map<int,int> code;
vector<int> dist;

int a[1 + nmax], b[1 + nmax];

void normalize(int n){
  vector<int> temp;
  temp.push_back(0);
  for(int i = 1; i <= n; i++){
    temp.push_back(a[i]);
    temp.push_back(b[i]);
  }
  sort(temp.begin(), temp.end());
  temp.erase(unique(temp.begin(), temp.end()), temp.end());
  dist = temp;
  for(int i = 0; i < temp.size(); i++)
    code[temp[i]] = i;
  for(int i = 1;i <= n; i++){
    a[i] = code[a[i]];
    b[i] = code[b[i]];
  }

}

ModuloRing choose[5 + 2 * nmax][1 + nmax];
ModuloRing dp[5 + nmax][5 + nmax];
ModuloRing fact[5 + nmax];

void computefact(){
  fact[0] = 1;
  for(int i = 1;i <= nmax; i++)
    fact[i] = fact[i - 1] * i;
}

ModuloRing comb(int n, int k){
  if(n < k)
    return 0;
  if(n <= nmax)
    return fact[n] / fact[k] / fact[n - k];

  ModuloRing result(1);
  for(int i = n - k + 1; i <= n; i++)
    result = result * i;
  for(int i = 1; i <= k; i++)
    result = result / i;
  return result;
}

int main()
{
  int n;
  cin >> n;
  for(int i = 1;i <= n; i++) {
    cin >> a[i] >> b[i];
    b[i]++;
  }
  normalize(n);
  computefact();

  for(int i = 1; i < dist.size() - 1; i++) {
    int d = dist[i + 1] - dist[i];
    for(int j = 1; j <= n; j++)
      for(int h = 1;h <= j; h++) {
        choose[i][j] = choose[i][j] + comb(j - 1, h - 1) * comb(d, h);
      }
  }

  for(int i = 0; i < dist.size() - 1; i++)
    dp[0][i] = 1;

  for(int i = 1;i <= n; i++){
    for(int j = a[i]; j < b[i]; j++){
      int _count = 1;
      for(int i2 = i - 1; 0 <= i2; i2--){
        dp[i][j] = dp[i][j] + dp[i2][j - 1] * choose[j][_count];
        if(a[i2] <= j && j < b[i2])
          _count++;
      }
    }
    for(int j = 1; j < dist.size() - 1; j++) {
      dp[i][j] = dp[i][j] + dp[i][j - 1];
    }
  }

  ModuloRing result(0);
  for(int i = 1;i <= n; i++)
    result = result + dp[i][dist.size() - 2];
  cout << result.number;
  return 0;
}

Compilation message

boat.cpp: In function 'void normalize(int)':
boat.cpp:69:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0; i < temp.size(); i++)
                  ~~^~~~~~~~~~~~~
boat.cpp: In function 'int main()':
boat.cpp:113:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 1; i < dist.size() - 1; i++) {
                  ~~^~~~~~~~~~~~~~~~~
boat.cpp:121:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0; i < dist.size() - 1; i++)
                  ~~^~~~~~~~~~~~~~~~~
boat.cpp:133:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int j = 1; j < dist.size() - 1; j++) {
                    ~~^~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Execution timed out 2085 ms 3328 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 2085 ms 3328 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1688 ms 3356 KB Output is correct
2 Correct 1692 ms 3320 KB Output is correct
3 Correct 1681 ms 3356 KB Output is correct
4 Correct 1688 ms 3448 KB Output is correct
5 Correct 1681 ms 3448 KB Output is correct
6 Correct 1684 ms 3448 KB Output is correct
7 Correct 1682 ms 3448 KB Output is correct
8 Correct 1684 ms 3448 KB Output is correct
9 Correct 1682 ms 3356 KB Output is correct
10 Correct 1679 ms 3448 KB Output is correct
11 Correct 1684 ms 3448 KB Output is correct
12 Correct 1687 ms 3424 KB Output is correct
13 Correct 1688 ms 3356 KB Output is correct
14 Correct 1686 ms 3328 KB Output is correct
15 Correct 1685 ms 3456 KB Output is correct
16 Correct 774 ms 3328 KB Output is correct
17 Correct 768 ms 3328 KB Output is correct
18 Correct 769 ms 3328 KB Output is correct
19 Correct 775 ms 3352 KB Output is correct
20 Correct 795 ms 3448 KB Output is correct
# Verdict Execution time Memory Grader output
1 Execution timed out 2085 ms 3328 KB Time limit exceeded
2 Halted 0 ms 0 KB -