Submission #672245

#	Time	Username	Problem	Language	Result	Execution time	Memory
672245		Dan4Life	Boat (APIO16_boat)	C++17	0 / 100	995 ms	524288 KiB

boat

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define fi first
#define se second
const int maxn = 5e2+10;
const int MOD = (int)1e9+7;
pair<int,int> a[maxn];
unordered_map<int,int> dp[maxn];
int n;

int32_t main() {
	cin >> n; int ans = 0;
	for(int i = 0; i < n; i++) cin >> a[i].fi >> a[i].se;
	for(int i = 0; i < n; i++){
		for(int j = a[i].fi; j <= a[i].se; j++){
			dp[i][j]=1; if(j>a[i].fi) dp[i][j]+=dp[i][j-1]; dp[i][j]%=MOD;
			for(int k = 0; k < i; k++) 
				if(j>a[k].fi) dp[i][j]+=dp[k][min(j-1,a[i].se)], dp[i][j]%=MOD;
		}
	}
	for(int i = 0; i < n; i++) ans+=dp[i][a[i].se], ans%=MOD;
	cout << ans;
}

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