oj.uz

Submission #1027527

# Submission time Handle Problem Language Result Execution time Memory
1027527 2024-07-19T07:17:03 Z _8_8_ Boat (APIO16_boat) C++17
27 / 100
 1256 ms 8584 KB 
#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
const int  N = 5e2 + 20, MOD = (int)1e9+7;
 
 
ll binpow(ll a,ll b) {
    ll ans = 1,k = a;
    while(b) {
        if(b % 2)ans *= k;
        ans %= MOD;
        k *= k;
        k %= MOD;
        b /= 2ll;
    }
    return ans;
}
ll bp[N];
ll mem[N][N];
ll ceis(ll n,ll k){
    if(k > n) return 0;
    if(n < N && mem[n][k]) return mem[n][k];     
    ll d = 1;
    for(ll i = n - k + 1;i <= n;i++){
        d = i % MOD * d % MOD;
    }
    for(ll i = 2;i <= k;i++){   
        d = d * bp[i]%MOD;
    }
    if(n < N){
        mem[n][k] = d;
    }
    return d;
}
int n;
array<int,2> a[N];
vector<int> b;
vector<array<int,2>> o;
ll dp[N][N],pref[N][N],c[N][N];
int m;
void test(){
    cin >> n;
    for(int i = 1;i <= n;i++){
        cin >> a[i][0] >> a[i][1];
        b.push_back(a[i][0]);
        b.push_back(a[i][1] + 1);
        bp[i] = binpow(i,MOD-2);
    }
    sort(b.begin(),b.end());
    b.resize(unique(b.begin(),b.end()) - b.begin()); 
    for(int i = 1;i < (int)b.size();i++){
        o.push_back({b[i-1],b[i]-1});
    }
    int m = (int)o.size();
    for(int i = 0;i <= m;i++){
        pref[0][i] = 1;
    }
    for(int i = 1;i <= m;i++){
        int s = (o[i - 1][1] - o[i - 1][0]+1);
        c[i][1] = s;
        vector<ll> C(n+1,0);
        for(int j = 0;j <= n;++j){
            C[j] = ceis(s,j);
        }
        for(int j = 2;j <= n;j++){
            for(int k = 0;k <= j-2;k++){
                c[i][j] = (c[i][j] + ceis(j-2,k)*C[j-k]%MOD)%MOD;
            }
        }
    }
    // return;
    for(int i = 1;i <= n;i++){
        pref[i][0] = 1;
        for(int j = 1;j <= m;j++){
            dp[i][j] = dp[i - 1][j];
            if(a[i][0] <= o[j - 1][0] && a[i][1] >= o[j-1][1]){
                for(int k = i,col = 0;k >= 1;k--){
                    if(a[k][0] <= o[j-1][0] && a[k][1] >= o[j-1][1]){
                        ++col;
                        dp[i][j] += pref[k-1][j-1]*c[j][col]%MOD;
                        // cout << j << ' ' << col << ' ' << c[j][col]%MOD << "x\n";
                        if(dp[j][j] >= MOD) dp[i][j] -= MOD;
                    }
                }
            }
        }
        for(int j = 1;j <= m;j++){
            // cout << dp[i][j] << ' ';
            pref[i][j] = (pref[i][j - 1] + dp[i][j])%MOD;
        }
        // cout << '\n';    
    }
    cout << (pref[n][m]-1+MOD)%MOD << '\n';
}
int main() {
    ios_base::sync_with_stdio(false);cin.tie(0);
    int t = 1; 
    // cin >> t;
    while(t--){
        test();
    }
}

Subtask #1
0 / 9.0

# Verdict Execution time Memory Grader output
1 Incorrect 1256 ms 8584 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Incorrect 1256 ms 8584 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 5208 KB Output is correct
2 Correct 16 ms 5468 KB Output is correct
3 Correct 16 ms 5256 KB Output is correct
4 Correct 16 ms 5208 KB Output is correct
5 Correct 16 ms 5260 KB Output is correct
6 Correct 17 ms 5256 KB Output is correct
7 Correct 17 ms 5460 KB Output is correct
8 Correct 18 ms 5212 KB Output is correct
9 Correct 17 ms 5208 KB Output is correct
10 Correct 17 ms 5392 KB Output is correct
11 Correct 18 ms 5208 KB Output is correct
12 Correct 18 ms 5208 KB Output is correct
13 Correct 16 ms 5212 KB Output is correct
14 Correct 16 ms 5260 KB Output is correct
15 Correct 17 ms 5468 KB Output is correct
16 Correct 9 ms 5212 KB Output is correct
17 Correct 10 ms 5256 KB Output is correct
18 Correct 9 ms 5212 KB Output is correct
19 Correct 9 ms 5384 KB Output is correct
20 Correct 9 ms 5212 KB Output is correct

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Incorrect 1256 ms 8584 KB Output isn't correct
2 Halted 0 ms 0 KB -