oj.uz

Submission #1106731

# Submission time Handle Problem Language Result Execution time Memory
1106731 2024-10-31T02:00:24 Z 12345678 Boat (APIO16_boat) C++17
9 / 100
 2000 ms 12672 KB 
#include <bits/stdc++.h>

using namespace std;

#define ll long long

const int nx=505, mod=1e9+7;
ll n, a[nx], b[nx], dp[nx][2*nx], qs[nx][2*nx], sz[2*nx], t, pv, ncr[nx][nx], choose[2*nx][nx], l[nx], r[nx];
map<ll, ll> mp;

ll invmod(ll a, ll x)
{
    if (x==0) return 1;
    auto tmp=invmod(a, x/2);
    tmp=(tmp*tmp)%mod;
    if (x%2) return (tmp*a)%mod;
    else return tmp;
}

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n;
    for (int i=1; i<=n; i++) cin>>a[i]>>b[i], mp[--a[i]]=0, mp[b[i]]=0;
    for (auto &[x, y]:mp) y=t, sz[t]=x-pv, pv=x, t++;
    for (int i=1; i<=n; i++) l[i]=mp[a[i]], r[i]=mp[b[i]];
    ncr[0][0]=1;
    for (int i=1; i<=n; i++)
    {
        for (int j=0; j<=i; j++)
        {
            ncr[i][j]=ncr[i-1][j];
            if (j>0) ncr[i][j]=(ncr[i][j]+ncr[i-1][j-1])%mod;
        }
    }
    for (int i=1; i<t; i++)
    {
        //cout<<"sz "<<i<<' '<<sz[i]<<'\n';
        ll tmp=1;
        choose[i][0]=tmp;
        for (int j=1; j<=min(sz[i], n); j++) tmp=(((tmp*(sz[i]-j+1))%mod)*invmod(j, mod-2))%mod, choose[i][j]=tmp;
    }
    for (int i=1; i<=n; i++)
    {
        //cout<<"l "<<i<<' '<<l[i]<<' '<<r[i]<<'\n';
        for (int j=1; j<t; j++)
        {
            if (l[i]<j&&j<=r[i])
            {
                dp[i][j]=((qs[i-1][j-1]+1)*sz[j])%mod;
                ll cnt=1;
                for (int k=i-1; k>=1; k--)
                {
                    if (l[k]<j&&j<=r[k]) cnt++;
                    //if (i==n) cout<<"debug "<<k<<' '<<cnt<<'\n';
                    if (cnt>=2)
                    {
                        ll sm=0;
                        for (int tmp=0; tmp<=cnt-2; tmp++) sm=(sm+choose[j][tmp+2]*ncr[cnt-2][tmp])%mod;
                        //if (i==n) cout<<"sm "<<sm<<'\n', cout<<"choose "<<choose[1][0]<<' '<<ncr[1][0]<<'\n';
                        dp[i][j]=(dp[i][j]+sm*(qs[k-1][j-1]+1))%mod;
                    }
                }
            }
            //cout<<"dp "<<i<<' '<<j<<' '<<dp[i][j]<<'\n';
            qs[i][j]=((dp[i][j]+qs[i-1][j]+qs[i][j-1]-qs[i-1][j-1])%mod+mod)%mod;
        }
    }
    cout<<qs[n][t-1];
}

/*
2
1 3
1 3
*/

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 57 ms 12360 KB Output is correct
2 Correct 58 ms 12156 KB Output is correct
3 Correct 57 ms 12368 KB Output is correct
4 Correct 57 ms 12368 KB Output is correct
5 Correct 57 ms 12360 KB Output is correct
6 Correct 55 ms 12616 KB Output is correct
7 Correct 57 ms 12668 KB Output is correct
8 Correct 56 ms 12616 KB Output is correct
9 Correct 58 ms 12616 KB Output is correct
10 Correct 57 ms 12616 KB Output is correct
11 Correct 57 ms 12616 KB Output is correct
12 Correct 58 ms 12672 KB Output is correct
13 Correct 56 ms 12616 KB Output is correct
14 Correct 56 ms 12616 KB Output is correct
15 Correct 56 ms 12664 KB Output is correct
16 Correct 16 ms 11088 KB Output is correct
17 Correct 19 ms 11052 KB Output is correct
18 Correct 16 ms 11088 KB Output is correct
19 Correct 16 ms 10980 KB Output is correct
20 Correct 17 ms 11088 KB Output is correct

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 57 ms 12360 KB Output is correct
2 Correct 58 ms 12156 KB Output is correct
3 Correct 57 ms 12368 KB Output is correct
4 Correct 57 ms 12368 KB Output is correct
5 Correct 57 ms 12360 KB Output is correct
6 Correct 55 ms 12616 KB Output is correct
7 Correct 57 ms 12668 KB Output is correct
8 Correct 56 ms 12616 KB Output is correct
9 Correct 58 ms 12616 KB Output is correct
10 Correct 57 ms 12616 KB Output is correct
11 Correct 57 ms 12616 KB Output is correct
12 Correct 58 ms 12672 KB Output is correct
13 Correct 56 ms 12616 KB Output is correct
14 Correct 56 ms 12616 KB Output is correct
15 Correct 56 ms 12664 KB Output is correct
16 Correct 16 ms 11088 KB Output is correct
17 Correct 19 ms 11052 KB Output is correct
18 Correct 16 ms 11088 KB Output is correct
19 Correct 16 ms 10980 KB Output is correct
20 Correct 17 ms 11088 KB Output is correct
21 Execution timed out 2062 ms 11088 KB Time limit exceeded
22 Halted 0 ms 0 KB -

Subtask #3
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 18 ms 5712 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 57 ms 12360 KB Output is correct
2 Correct 58 ms 12156 KB Output is correct
3 Correct 57 ms 12368 KB Output is correct
4 Correct 57 ms 12368 KB Output is correct
5 Correct 57 ms 12360 KB Output is correct
6 Correct 55 ms 12616 KB Output is correct
7 Correct 57 ms 12668 KB Output is correct
8 Correct 56 ms 12616 KB Output is correct
9 Correct 58 ms 12616 KB Output is correct
10 Correct 57 ms 12616 KB Output is correct
11 Correct 57 ms 12616 KB Output is correct
12 Correct 58 ms 12672 KB Output is correct
13 Correct 56 ms 12616 KB Output is correct
14 Correct 56 ms 12616 KB Output is correct
15 Correct 56 ms 12664 KB Output is correct
16 Correct 16 ms 11088 KB Output is correct
17 Correct 19 ms 11052 KB Output is correct
18 Correct 16 ms 11088 KB Output is correct
19 Correct 16 ms 10980 KB Output is correct
20 Correct 17 ms 11088 KB Output is correct
21 Execution timed out 2062 ms 11088 KB Time limit exceeded
22 Halted 0 ms 0 KB -