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Submission #291240

# Submission time Handle Problem Language Result Execution time Memory
291240 2020-09-04T23:33:48 Z penguinhacker Klasika (COCI20_klasika) C++17
33 / 110
 5000 ms 133160 KB 
#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define ar array

const int MAXDIG=30;
struct Node {
	int cnt=0;
	int nxt[2];
	Node() {nxt[0]=nxt[1]=-1;}
};
struct Trie {
	vector<Node> trie;
	Trie() {trie.emplace_back();}
	void reset() {trie.clear(); trie.emplace_back();}
	void add(int x) {
		int cur=0;
		++trie[0].cnt;
		for (int i=MAXDIG; ~i; --i) {
			int c=(x>>i)&1;
			if (trie[cur].nxt[c]==-1) {
				trie[cur].nxt[c]=trie.size();
				trie.emplace_back();
			}
			cur=trie[cur].nxt[c];
			++trie[cur].cnt;
		}
	}

	/*void remove(int x) {
		int cur=0;
		--trie[0].cnt;
		for (int i=MAXDIG; ~i; --i) {
			int c=(x>>i)&1;
			assert(trie[cur].nxt[c]!=-1);
			cur=trie[cur].nxt[c];
			--trie[cur].cnt;
		}
	}*/

	int qry(int x) { //best xor in trie 
		int cur=0;
		int res=0;
		for (int i=MAXDIG; ~i; --i) {
			int c=(x>>i)&1;
			if (trie[cur].nxt[c^1]!=-1&&trie[trie[cur].nxt[c^1]].cnt>0) {
				res+=(1<<i);
				cur=trie[cur].nxt[c^1];
			}
			else {
				cur=trie[cur].nxt[c];
			}
		}
		return res;
	}
};

//try to rebuild every sqrt(n) queries, change block size to pass constraints
const int mxN=2e5;
int totNodes=1, n, val[mxN], parent[mxN];
int pos[mxN], iPos[mxN], sz[mxN], tin[mxN], tout[mxN];
bool vis[mxN];
vector<int> adj[mxN];
Trie tree[4*mxN];

void dfs(int u, int& ind, int& timer) {
	pos[u]=ind++;
	iPos[pos[u]]=u;
	tin[u]=timer++;
	sz[u]=1;
	for (int v : adj[u]) {
		dfs(v, ind, timer);
		sz[u]+=sz[v];
	}
	tout[u]=timer++;
}

void buildTree(int u=1, int l=0, int r=n-1) { //takes n*log(n)*31 time around
	tree[u].reset();
	for (int i=l; i<=r; ++i) {
		tree[u].add(val[iPos[i]]);
	}
	if (l==r) return;
	int mid=(l+r)/2;
	buildTree(2*u, l, mid), buildTree(2*u+1, mid+1, r);
}

int qry(int ql, int qr, int x, int u=1, int l=0, int r=n-1) { //take log(n)*31 time around
	if (l>qr||r<ql) return 0;
	if (ql<=l&&r<=qr) return tree[u].qry(x);
	int mid=(l+r)/2;
	return max(qry(ql, qr, x, 2*u, l, mid), qry(ql, qr, x, 2*u+1, mid+1, r));
}

vector<int> toCheck;
void rebuild() {
	n=totNodes;
	int ind=0, timer=0;
	dfs(0, ind, timer);
	buildTree();
	for (int i: toCheck) vis[i]=1;
	toCheck.clear();
}

int brute(int u, int x) {
	int res=x^val[u];
	for (int v: adj[u]) res=max(res, brute(v, x));
	return res;
}

int temp[mxN];

int dfs_check(int b, int x) {
	if (vis[x]) {
		return tin[b]<=tin[x]&&tout[b]>=tout[x];
	}
	return temp[x]=dfs_check(b, parent[x]);
}

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);

	fill(temp, temp+mxN, -1);
	int q; cin >> q;
	while(q--) {
		string type; cin >> type;
		int a, b; cin >> a >> b;
		if (type=="Add") {
			--a;
			val[totNodes]=val[a]^b;
			adj[a].push_back(totNodes);
			parent[totNodes]=a;
			toCheck.push_back(totNodes);
			++totNodes;
			//rebuild();
			if (totNodes%2000==0) rebuild();
		}
		if (type=="Query") {
			--a, --b;
			int ans=0;
			if (vis[b]) {
				int l=pos[b], r=pos[b]+sz[b]-1;
				ans=qry(l, r, val[a]);
				for (int i: toCheck) {
					if (temp[i]==-1) dfs_check(b, i);
					if (temp[i]) {
						ans=max(ans, val[i]^val[a]);
					}
				}
				for (int i: toCheck) temp[i]=-1;
			}
			else {
				ans=brute(b, val[a]);
			}
			cout << ans << "\n";
			//cout << "testing\n";
		}
	}
	return 0;
}

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 62 ms 49656 KB Output is correct
2 Correct 62 ms 49656 KB Output is correct
3 Correct 62 ms 49656 KB Output is correct
4 Correct 61 ms 49656 KB Output is correct
5 Correct 61 ms 49660 KB Output is correct
6 Correct 61 ms 49656 KB Output is correct
7 Correct 61 ms 49656 KB Output is correct
8 Correct 61 ms 49656 KB Output is correct
9 Correct 61 ms 49720 KB Output is correct
10 Correct 61 ms 49656 KB Output is correct
11 Correct 62 ms 49784 KB Output is correct
12 Correct 61 ms 49656 KB Output is correct

Subtask #2
22.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 62 ms 49656 KB Output is correct
2 Correct 62 ms 49656 KB Output is correct
3 Correct 62 ms 49656 KB Output is correct
4 Correct 61 ms 49656 KB Output is correct
5 Correct 61 ms 49660 KB Output is correct
6 Correct 61 ms 49656 KB Output is correct
7 Correct 61 ms 49656 KB Output is correct
8 Correct 61 ms 49656 KB Output is correct
9 Correct 61 ms 49720 KB Output is correct
10 Correct 61 ms 49656 KB Output is correct
11 Correct 62 ms 49784 KB Output is correct
12 Correct 61 ms 49656 KB Output is correct
13 Correct 62 ms 49784 KB Output is correct
14 Correct 65 ms 49816 KB Output is correct
15 Correct 67 ms 49784 KB Output is correct
16 Correct 66 ms 49784 KB Output is correct
17 Correct 63 ms 49656 KB Output is correct
18 Correct 62 ms 49784 KB Output is correct
19 Correct 62 ms 49784 KB Output is correct
20 Correct 62 ms 49784 KB Output is correct
21 Correct 64 ms 49656 KB Output is correct
22 Correct 63 ms 49784 KB Output is correct
23 Correct 64 ms 49752 KB Output is correct
24 Correct 62 ms 49784 KB Output is correct

Subtask #3
0 / 33.0

# Verdict Execution time Memory Grader output
1 Execution timed out 5063 ms 133160 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 44.0

# Verdict Execution time Memory Grader output
1 Correct 62 ms 49656 KB Output is correct
2 Correct 62 ms 49656 KB Output is correct
3 Correct 62 ms 49656 KB Output is correct
4 Correct 61 ms 49656 KB Output is correct
5 Correct 61 ms 49660 KB Output is correct
6 Correct 61 ms 49656 KB Output is correct
7 Correct 61 ms 49656 KB Output is correct
8 Correct 61 ms 49656 KB Output is correct
9 Correct 61 ms 49720 KB Output is correct
10 Correct 61 ms 49656 KB Output is correct
11 Correct 62 ms 49784 KB Output is correct
12 Correct 61 ms 49656 KB Output is correct
13 Correct 62 ms 49784 KB Output is correct
14 Correct 65 ms 49816 KB Output is correct
15 Correct 67 ms 49784 KB Output is correct
16 Correct 66 ms 49784 KB Output is correct
17 Correct 63 ms 49656 KB Output is correct
18 Correct 62 ms 49784 KB Output is correct
19 Correct 62 ms 49784 KB Output is correct
20 Correct 62 ms 49784 KB Output is correct
21 Correct 64 ms 49656 KB Output is correct
22 Correct 63 ms 49784 KB Output is correct
23 Correct 64 ms 49752 KB Output is correct
24 Correct 62 ms 49784 KB Output is correct
25 Execution timed out 5063 ms 133160 KB Time limit exceeded
26 Halted 0 ms 0 KB -