Submission #394100

#	Time	Username	Problem	Language	Result	Execution time	Memory
394100		jeqcho	Boat (APIO16_boat)	C++17	0 / 100	5 ms	4300 KiB

boat

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<pair<int,int>> vpi;

#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)

#define pb push_back
#define rsz resize
#define sz(x) int(x.size())
#define all(x) begin(x), end(x)
#define fi first
#define se second

int const N=5e2+3;
int const A=1e3+3;
int a[N],b[N];
ll dp[N][2*N];
ll mod =1e9+7;
bitset<2*N> vis[N];
int n;

ll recur(int now, int mx)
{
	if(now==n)
	{
		return 1;
	}
	if(vis[now][mx])return dp[now][mx];
	vis[now][mx]=1;
	ll ans=recur(now+1,mx);
	if(mx<a[now])
	{
		ans+=recur(now+1,a[now]);
	}
	dp[now][mx]=ans;
	return ans;
}

int main()
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	cin>>n;
	set<int> st;
	F0R(i,n)
	{
		cin>>a[i]>>b[i];
		st.insert(a[i]);
		st.insert(b[i]);
	}
	map<int,int>mp;
	int idx=1;
	trav(e,st)
	{
		mp[e]=idx;
		++idx;
	}
	F0R(i,n)
	{
		a[i]=mp[a[i]];
		b[i]=mp[b[i]];
	}
	cout<<recur(0,0)<<'\n';
	return 0;
}

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