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Submission #920553

# Submission time Handle Problem Language Result Execution time Memory
920553 2024-02-02T17:48:27 Z irmuun Boat (APIO16_boat) C++17
27 / 100
 2000 ms 8284 KB 
#include<bits/stdc++.h>
 
using namespace std;
 
#define ll long long
#define pb push_back
#define ff first
#define ss second
#define all(s) s.begin(),s.end()
#define rall(s) s.rbegin(),s.rend()

const ll mod=1e9+7,N=1e3+5;

ll binpow(ll a,ll b){
    ll res=1;
    while(b){
        if(b&1){
            res=res*a%mod;
        }
        a=a*a%mod;
        b=b>>1;
    }
    return res;
}
ll inv(ll a){
    return binpow(a,mod-2);
}

ll fact[N],invfact[N];

void init(){
    fact[0]=1;
    for(ll i=1;i<N;i++){
        fact[i]=fact[i-1]*i%mod;
    }
    invfact[N-1]=inv(fact[N-1]);
    for(ll i=N-1;i>=1;i--){
        invfact[i-1]=invfact[i]*i%mod;
    }
}
ll nCk(ll n,ll k){
    if(k>n||k<0) return 0ll;
    ll res=1;
    for(ll i=n-k+1;i<=n;i++) res=res*i%mod;
    res=res*invfact[k]%mod;
    return res;
}

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    init();
    ll n;
    cin>>n;
    ll a[n+5],b[n+5];
    set<ll>s;
    for(ll i=1;i<=n;i++){
        cin>>a[i]>>b[i];
        s.insert(a[i]);
        s.insert(b[i]+1);
    }
    ll cur=0;
    ll l[2*n+5];
    for(auto x:s){
        cur++;
        l[cur]=x;
    }
    ll dp[2*n+5][n+5],sum[2*n+5][n+5];
    memset(sum,0,sizeof sum);
    ll ans=0;
    for(ll i=1;i<=n;i++){
        ll tot=1;
        memset(dp,0,sizeof dp);
        for(ll j=1;j<cur;j++){//l[j] l[j+1]-1
            if(b[i]>=l[j]&&a[i]<l[j+1]){
                dp[j][1]=tot;
                for(ll k=2;k<=n;k++){
                    dp[j][k]=sum[j][k-1];
                }
            }
            for(ll k=1;k<=n;k++){
                tot+=sum[j][k]*nCk(l[j+1]-l[j],k)%mod;
                tot%=mod;
            }
            for(ll k=1;k<=n;k++){
                sum[j][k]+=dp[j][k];
                sum[j][k]%=mod;
            }
        }
    }
    for(ll j=1;j<cur;j++){
        for(ll k=1;k<=n;k++){
            ans+=sum[j][k]*nCk(l[j+1]-l[j],k)%mod;
            ans%=mod;
        }
    }
    cout<<ans;
}

Subtask #1
0 / 9.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2035 ms 8284 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2035 ms 8284 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #3
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 365 ms 788 KB Output is correct
2 Correct 360 ms 604 KB Output is correct
3 Correct 362 ms 600 KB Output is correct
4 Correct 361 ms 600 KB Output is correct
5 Correct 361 ms 600 KB Output is correct
6 Correct 364 ms 600 KB Output is correct
7 Correct 362 ms 604 KB Output is correct
8 Correct 361 ms 792 KB Output is correct
9 Correct 361 ms 788 KB Output is correct
10 Correct 363 ms 788 KB Output is correct
11 Correct 363 ms 856 KB Output is correct
12 Correct 362 ms 792 KB Output is correct
13 Correct 367 ms 784 KB Output is correct
14 Correct 364 ms 788 KB Output is correct
15 Correct 364 ms 784 KB Output is correct
16 Correct 159 ms 788 KB Output is correct
17 Correct 158 ms 600 KB Output is correct
18 Correct 159 ms 796 KB Output is correct
19 Correct 158 ms 604 KB Output is correct
20 Correct 163 ms 784 KB Output is correct

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2035 ms 8284 KB Time limit exceeded
2 Halted 0 ms 0 KB -