oj.uz

Submission #1027504

# Submission time Handle Problem Language Result Execution time Memory
1027504 2024-07-19T07:08:42 Z _8_8_ Boat (APIO16_boat) C++17
27 / 100
 2000 ms 5456 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});
        // cout << b[i-1] << ' ' << b[i]-1 << '\n';
    }
    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;
        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)*ceis(s,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 Execution timed out 2055 ms 4692 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 2055 ms 4692 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #3
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 296 ms 5200 KB Output is correct
2 Correct 299 ms 5456 KB Output is correct
3 Correct 291 ms 5200 KB Output is correct
4 Correct 302 ms 5200 KB Output is correct
5 Correct 298 ms 5204 KB Output is correct
6 Correct 305 ms 5364 KB Output is correct
7 Correct 305 ms 5424 KB Output is correct
8 Correct 293 ms 5388 KB Output is correct
9 Correct 298 ms 5200 KB Output is correct
10 Correct 300 ms 5236 KB Output is correct
11 Correct 295 ms 5204 KB Output is correct
12 Correct 292 ms 5224 KB Output is correct
13 Correct 300 ms 5232 KB Output is correct
14 Correct 294 ms 5204 KB Output is correct
15 Correct 262 ms 5200 KB Output is correct
16 Correct 136 ms 5396 KB Output is correct
17 Correct 133 ms 5200 KB Output is correct
18 Correct 132 ms 5204 KB Output is correct
19 Correct 131 ms 5200 KB Output is correct
20 Correct 138 ms 5204 KB Output is correct

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2055 ms 4692 KB Time limit exceeded
2 Halted 0 ms 0 KB -