Submission #1187893

#	Time	Username	Problem	Language	Result	Execution time	Memory
1187893		thelegendary08	Cat Exercise (JOI23_ho_t4)	C++17	0 / 100	0 ms	324 KiB

Main

#include<bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define int long long
#define vi vector<int>
#define vvi vector<vector<int>>
#define pii pair<int, int>
#define vpii vector<pair<int, int>>
#define vc vector<char>
#define vb vector<bool>
#define mii map<int,int>
#define f0r(i,n) for(int i=0;i<n;i++)
#define FOR(i,k,n) for(int i=k;i<n;i++)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define in(a) int a; cin>>a
#define in2(a,b) int a,b; cin>>a>>b
#define in3(a,b,c) int a,b,c; cin>>a>>b>>c
#define in4(a,b,c,d) int a,b,c,d; cin>>a>>b>>c>>d
#define vin(v,n); vi v(n); f0r(i,n){cin>>v[i];}
#define out(a) cout<<a<<'\n'
#define out2(a,b) cout<<a<<' '<<b<<'\n'
#define out3(a,b,c) cout<<a<<' '<<b<<' '<<c<<'\n'
#define out4(a,b,c,d) cout<<a<<' '<<b<<' '<<c<<' '<<d<<'\n'
#define pout(a) cout<<a.first<<' '<<a.second<<'\n'
#define vout(v) for(auto u : v){cout<<u<<' ';} cout<<'\n'
#define dout(a) cout<<a<<' '<<#a<<'\n'
#define dout2(a,b) cout<<a<<' '<<#a<<' '<<b<<' '<<#b<<'\n'
#define yn(x); if(x){cout<<"YES"<<'\n';}else{cout<<"NO"<<'\n';}
const int leg = 1e9 + 7;
const int mod = 998244353;
using namespace std;
struct maxsegtree{
	vpii tree;
	int n;
	void update(int k, int x){
		k += n;
		tree[k] = mp(x,k-n);
		for(k/=2;k>=1;k/=2){
			tree[k] = max(tree[k*2], tree[k*2+1]);
		}
	}
	int quer(int l, int r){
		pii ret = {-1,-1};
		l+=n; r+=n;
		while(l<=r){
			if(l % 2 == 1)ret = max(ret, tree[l++]);
			if(r % 2 == 0)ret = max(ret, tree[r--]);
			l/=2; r/=2;
		}
		return ret.second;
	}
	
	maxsegtree(vi &a){
		n = a.size();
		tree.resize(2*n+5);
		f0r(i,n)update(i, a[i]);
	}
};

struct DSU{
	int n;
	vi par;
	vi sz;
	vpii rng;
	DSU(int x){
		n = x;
		par.resize(x);
		sz.resize(x);
		rng.resize(x);
		f0r(i,x){
			par[i] = i;
			sz[i] = 1;
			rng[i] = mp(i,i);
		}
	}
	int find(int x){
		while(x != par[x])x = par[x];
		return x;
	}
	pii r(int x){
		x = find(x);
		return rng[x];
	}
	void unite(int a, int b){
		a = find(a);
		b = find(b);
		if(a == b)return;
		if(sz[a] < sz[b])swap(a,b);
		sz[a] += sz[b];
		par[b] = a;
		rng[a] = mp(min(rng[a].first, rng[b].first), max(rng[a].second,rng[b].second));
	}
};
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	//ifstream cin(".in");
	//ofstream cout(".out");
	in(n);
	vin(v,n);
	vvi adj(n);
	f0r(i,n-1){
		in2(a,b);
		a--; b--;
		adj[a].pb(b);
		adj[b].pb(a);
	}
	f0r(i,n){
		v[i]--;
	}
	maxsegtree t = maxsegtree(v);
	DSU d = DSU(n);
	vi numtonode(n);
	f0r(i,n){
		numtonode[v[i]] = i;
	}
	vector<vpii> nxt(n);
	
	f0r(i,n){
		int g = numtonode[i];
		if(numtonode[i] != 0 && v[numtonode[i] - 1] < i){
			d.unite(g-1, g);
		}
		if(numtonode[i] != n-1 && v[numtonode[i] + 1] < i){
			d.unite(g, g+1);
		}
		
		pii rng = d.r(numtonode[i]);
		if(numtonode[i] != rng.first){
			int mxd = t.quer(rng.first, numtonode[i]-1);
			nxt[i].pb(mp(v[mxd], i - mxd));
		}
		if(numtonode[i] != rng.second){
			int mxd = t.quer(numtonode[i] + 1, rng.second);
			nxt[i].pb(mp(v[mxd], mxd - i));
		}
		
	}
	
	vi dp(n);
	dp[n-1] = 0;
	for(int i = n-1; i>=0; i--){
		// dout(i);
		for(pii x : nxt[i]){
			// pout(x);
			dp[x.first] = max(dp[x.first], dp[i] + x.second);
		}
		// cout<<'\n';
	}
	
	
	out(*max_element(all(dp)));
	
}

• Subtask 1: 0 / 7
• Subtask 2: 0 / 7
• Subtask 3: 0 / 7
• Subtask 4: 0 / 10
• Subtask 5: 0 / 20
• Subtask 6: 0 / 23
• Subtask 7: 0 / 26