Submission #95326

#	Time	Username	Problem	Language	Result	Execution time	Memory
95326		tduong0806	Boat (APIO16_boat)	C++14	0 / 100	6 ms	4344 KiB

boat

#include <bits/stdc++.h>
typedef long long ll;
typedef unsigned long long ull;
using namespace std;
#define forinc(a,b,c) for(int a=b,_c=c;a<=_c;++a)
#define fordec(a,b,c) for(int a=b,_c=c;a>=_c;--a)
#define all(a) a.begin(),a.end()
#define pb push_back
const int N=1010,mod=1e9+7;
int n,f[N][N],a[N],b[N],old[N],s[N][N],m;
vector<int> e;
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    //freopen("BOAT.inp","r",stdin);
    //freopen("BOAT.out","w",stdout);
    cin>>n;
    forinc(i,1,n)
    {
        cin>>a[i]>>b[i];
        e.pb(a[i]);e.pb(b[i]);
    }
    e.erase(unique(all(e)),e.end());
    m=e.size();
    forinc(i,0,m-1)
    {
        old[i+1]=e[i];
        a[i]=lower_bound(all(e),a[i])-e.begin()+1;
        b[i]=lower_bound(all(e),b[i])-e.begin()+1;
    }
    old[m+1]=1e9;
    f[0][0]=1;
    forinc(j,0,m) s[0][j]=1;
    forinc(i,1,n) forinc(j,0,m)
    {
        f[i][j]=(f[i][j]+f[i-1][j])%mod;
        if(j>=a[i]&&j<=b[i])
        {
            int c=min(old[b[i]],old[j+1]-1);
            f[i][j]=(f[i][j]+s[i-1][j-1]*(c-old[j]+1))%mod;
        }
        s[i][j]=s[i][j-1]+f[i][j];
    }
    cout<<s[n][m]-1;
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 22
• Subtask 3: 0 / 27
• Subtask 4: 0 / 42