Submission #3419800


Source Code Expand

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<cstdlib>
#include<cmath>
#include<cstring>
#include<set>
#include<map>
#include<queue>
using namespace std;
#define rep(i,n) for(int (i)=0;(i)<(n);++i)
#define rrep(i,n) for(int (i)=(n)-1;(i)>=0;--i)
#define rep1(i,n) for(int (i)=1;(i)<=(n);++i)
#define rrep1(i,n) for(int (i)=(n);(i)>=1;--i)
#define pb push_back
#define fr first
#define sc second
typedef int ss;
#define int long long

typedef long long ll;
typedef pair<int,int> P;
typedef pair<long long,long long> LP;
typedef double db;
using namespace std;

ll N;
ll A[100000];
ll B[100000];
vector<ll> xs;
ll w[200000];
vector<ll> F;
ll mod = 1e+9 + 7;
ll jo[200001];

int extgcd(int a,int b,int& x,int& y){
  int d=a;
  if(b != 0){
    d = extgcd( b , a%b, y, x);
    y -= (a/b)*x;
  } else{
    x=1; y=0;
  }
  return d;
}

int mod_inverse(int a,int m){
  int x,y;
  extgcd(a,m,x,y);
  return (m+x%m) %m;
}

ll comb(ll n,ll r){
  return (((jo[n]*mod_inverse(jo[r],mod)) %mod) *mod_inverse(jo[n-r],mod))%mod;
}

ss main()
{
  cin>>N;
  jo[0]=jo[1]=1LL;
  rep1(i,2*N){
    jo[i]= (jo[i-1]*i) %mod;
  }
  rep(i,N){
    cin>>A[i];
    xs.pb(A[i]);
  }
  rep(i,N){
    cin>>B[i];
    xs.pb(B[i]);
  }
  sort(xs.begin(),xs.end());
  xs.erase( unique(xs.begin(),xs.end()) , xs.end() );
  rep(i,N){
    A[i] = lower_bound(xs.begin(),xs.end(),A[i]) - xs.begin();
    B[i] = lower_bound(xs.begin(),xs.end(),B[i]) - xs.begin();
    w[A[i]]=0;
    w[B[i]]=1;
  }
  ll cnt;
  for(int i = 0; i< 2*N ;i++){
    cnt = 1LL;
    while(i + 1 < 2*N && w[i] == w[i+1] ){
      i++;
      cnt++;
    }
    F.pb(cnt);
  }
  ll ans = 1LL;
  rep(i,F.size()-1){
    if( F[i] <= F[i+1] ){
      ans = (ans * jo[F[i]])%mod;
      F[i+1]-=F[i];
    }
    else{
      ans = (((ans * jo[F[i+1]])%mod)*comb(F[i],F[i+1]))%mod;
      F[i+2] += (F[i]-F[i+1]);
      F[i] = F[i+1] = 0;
    }
  }
  cout<<ans<<endl;
}

Submission Info

Submission Time
Task A - 1D Matching
User miyajiro
Language C++14 (GCC 5.4.1)
Score 500
Code Size 2043 Byte
Status AC
Exec Time 150 ms
Memory 9584 KB

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 500 / 500
Status
AC × 2
AC × 14
Set Name Test Cases
Sample example0.txt, example1.txt
All 000.txt, 001.txt, 002.txt, 003.txt, 004.txt, 005.txt, 006.txt, 007.txt, 008.txt, 009.txt, 010.txt, 011.txt, example0.txt, example1.txt
Case Name Status Exec Time Memory
000.txt AC 90 ms 6004 KB
001.txt AC 32 ms 3704 KB
002.txt AC 45 ms 4344 KB
003.txt AC 50 ms 4724 KB
004.txt AC 133 ms 7792 KB
005.txt AC 149 ms 8304 KB
006.txt AC 150 ms 8304 KB
007.txt AC 149 ms 8304 KB
008.txt AC 150 ms 8304 KB
009.txt AC 150 ms 8304 KB
010.txt AC 124 ms 6644 KB
011.txt AC 129 ms 9584 KB
example0.txt AC 2 ms 2304 KB
example1.txt AC 2 ms 2304 KB