Submission #1187931

#	Time	Username	Problem	Language	Result	Execution time	Memory
1187931		thelegendary08	Cat Exercise (JOI23_ho_t4)	C++17	100 / 100	337 ms	88048 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;
vvi adj;
const int mxn = 2e5 + 5;
vi dep(mxn);
vvi jmp(mxn, vi(18));
vi par(mxn);
void dfs(int node, int from){
	par[node] = from;
	for(auto u : adj[node]){
		if(u != from){
			dep[u] = dep[node] + 1;
			dfs(u, node);
		}
	}
}
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]);
	}
};
vector<vpii>nxt;
int dis(int a, int b){
	if(dep[a] < dep[b])swap(a,b);
	int diff = dep[a] - dep[b];
	int dist = 0;
	f0r(i, 18){
		if((1<<i) & diff){
			a = jmp[a][i];
			dist += (1 << i);
		}
	}
	if(a == b){
		return dist;
	}
	for(int i = 17; i>=0; i--){
		if(jmp[a][i] != jmp[b][i]){
			a = jmp[a][i];
			b = jmp[b][i];
			dist += (1 << (i + 1));
		}
	}
	dist += 2;
	return dist;
}
struct DSU{
	int n;
	vi par;
	vi sz;
	vpii mx;
	DSU(int x, vi &a){
		n = x;
		par.resize(x);
		sz.resize(x);
		mx.resize(x);
		f0r(i,x){
			par[i] = i;
			sz[i] = 1;
			mx[i] = mp(a[i],i);
		}
	}
	int find(int x){
		while(x != par[x])x = par[x];
		return x;
	}
	void unite(int a, int b, int val){
		int m = a;
		a = find(a);
		b = find(b);
		int thing = mx[b].second;
		nxt[val].pb(mp(mx[b].first, dis(m, thing)));
		if(a == b)return;
		if(sz[a] < sz[b])swap(a,b);
		sz[a] += sz[b];
		par[b] = a;
		mx[a] = max(mx[a], mx[b]);
	}
};




signed main(){
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	//ifstream cin(".in");
	//ofstream cout(".out");
	in(n);
	vin(v,n);
	adj.resize(n);
	f0r(i,n-1){
		in2(a,b);
		a--; b--;
		adj[a].pb(b);
		adj[b].pb(a);
	}
	f0r(i,n){
		v[i]--;
	}
	dep[0] = 0;
	dfs(0, -1);
	
	f0r(i,n){
		jmp[i][0] = par[i];
	}
	FOR(i, 1, 18){
		f0r(j,n){
			if(jmp[j][i-1] == -1)jmp[j][i] = -1;
			else jmp[j][i] = jmp[jmp[j][i-1]][i-1];
		}
	}
	
	
	maxsegtree t = maxsegtree(v);
	DSU d = DSU(n, v);
	vi numtonode(n);
	f0r(i,n){
		numtonode[v[i]] = i;
	}
	nxt.resize(n);
	f0r(i,n){
		int g = numtonode[i];
		
		for(auto u : adj[g]){
			if(v[u] < i){
				d.unite(g, u, 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: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 7 / 7
• Subtask 4: 10 / 10
• Subtask 5: 20 / 20
• Subtask 6: 23 / 23
• Subtask 7: 26 / 26