Submission #403138

#	Time	Username	Problem	Language	Result	Execution time	Memory
403138		amunduzbaev	Boat (APIO16_boat)	C++14	9 / 100	1707 ms	5608 KiB

boat

/* made by amunduzbaev */

//~ #include <ext/pb_ds/assoc_container.hpp>
//~ #include <ext/pb_ds/tree_policy.hpp>

#include "bits/stdc++.h"

using namespace std;
//~ using namespace __gnu_pbds;

#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define NeedForSpeed ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define vv vector
#define tut(x) array<int, x> 
#define int long long

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii; 
typedef vector<int> vii;
typedef vector<pii> vpii;
template<class T> bool umin(T& a, const T& b) {return a > b? a = b, true:false;}
template<class T> bool umax(T& a, const T& b) {return a < b? a = b, true:false;}
//~ void usaco(string s) { freopen((s+".in").c_str(),"r",stdin);  
	//~ freopen((s+".out").c_str(),"w",stdout); NeedForSpeed }
//~ template<class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

const int N = 505;
const int mod = 1e9+7; 
const ll inf = 1e18;
const ld Pi = acos(-1);
const int B = 455;

#define MULTI 0
int n, m, k, s, t, q, ans, res, a[N];
int b[N];
map<int, int> dp[N];

void solve(int t_case){
	cin>>n;
	vii tmp, tt;
	for(int i=0;i<n;i++) cin>>a[i]>>b[i];
	for(int i=0;i<n;i++) tmp.pb(a[i]), tmp.pb(b[i]);
	sort(all(tmp));
	for(int i=0;i<2*n;){
		int j = i;
		while(j < 2*n && tmp[j] == tmp[i]) j++;
		tt.pb(tmp[i]);
		i = j;
	}
	
	dp[0][a[0]] = 1;
	dp[0][b[0]] = (b[0] - a[0] + 1);
	
	for(int i=1;i<n;i++){
		vii tmp, tt;
		for(int j=0;j<=i;j++){
			if(a[j] >= a[i] && a[j] <= b[i]) tmp.pb(a[j]);
			if(b[j] >= a[i] && b[j] <= b[i]) tmp.pb(b[j]);
		}
		sort(all(tmp));
		for(int i=0;i<sz(tmp);){
			int j = i;
			while(j < sz(tmp) && tmp[j] == tmp[i]) j++;
			tt.pb(tmp[i]);
			i = j;
		}
		
		int cost = 0;
		for(auto x : tt){
			cost = (cost + 1) % mod;
			for(int j=0;j<i;j++){
				auto it = dp[j].lb(x);
				if(it != dp[j].begin()) --it, cost = (cost + (*it).ss) % mod;
			} dp[i][x] = cost;
		}
	}
	
	for(int i=0;i<n;i++){
		res = (res + (*--dp[i].end()).ss) % mod;
	} cout<<res<<"\n";
}

signed main(){
	NeedForSpeed
	if(MULTI){
		int t; cin>>t;
		for(int t_case = 1; t_case <= t; t_case++) solve(t_case);
	} else solve(1);
	return 0;
}

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