oj.uz

Submission #1086881

# Submission time Handle Problem Language Result Execution time Memory
1086881 2024-09-11T16:19:21 Z Drifter24 Palindromes (APIO14_palindrome) C++14
100 / 100
 23 ms 36904 KB 
#include <bits/stdc++.h>
using namespace std;
#define print(arr) for(auto& x:arr)cout<<x<<" ";cout<<"\n"
#define watch(x) cout<<#x<<"="<<x<<"\n"
#define all(x) x.begin(), x.end()
#define sz(x) ((int) x.size())
typedef long long ll;
typedef vector<ll> vl;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<ii> vii;

const int alpha = 26;
const char fc = 'a';

struct Node{
    int next[alpha];
    int len,link,dep,cnt;
};

struct PalindromeTree{
	vector<Node> tree; 
	string s;
	int len,n;
	int size;            // node 1 - root with len -1, node 2 - root with len 0
	int suff;           // max suffix palindrome

	bool addLetter(int pos){
		int cur=suff,curlen=0;
		int let=s[pos]-fc;
		while(true){
			curlen=tree[cur].len;
			if(pos-1-curlen>=0 && s[pos-1-curlen]==s[pos])break;  
			cur=tree[cur].link;
		}      

		if(tree[cur].next[let]){  
			suff=tree[cur].next[let];
			tree[suff].cnt++;
			return false;
		}

		size++;
		suff=size;
		tree[size].len=tree[cur].len+2;
		tree[cur].next[let]=size;
		tree[size].cnt=1;

		if(tree[size].len==1){
			tree[size].link=2;
			tree[size].dep=1;
			return true;
		}

		while(true){
			cur=tree[cur].link;
			curlen=tree[cur].len;
			if(pos-1-curlen>=0 && s[pos-1-curlen]==s[pos]){
				tree[size].link=tree[cur].next[let];
				break;
			}       
		}           

		tree[size].dep=1+tree[tree[size].link].dep;
		return true;
	}

	void build(string s2, int n){
		tree.assign(n+4,Node());
		tree[1].len=-1;tree[1].link=1;
		tree[2].len=0;tree[2].link=1;
		size=2;suff=2;s=s2;

		for(int i=0;i<n;i++){
			addLetter(i);
		}

		for(int i=size;i>=3;i--){
			tree[tree[i].link].cnt+=tree[i].cnt;
		}
	}
};


int main(){
	ios::sync_with_stdio(false);cin.tie(nullptr);
    string s;
	cin>>s;
	PalindromeTree pt;
	pt.build(s,sz(s));
	ll ans=0;
	for(int i=3;i<=pt.size;i++){
		ans=max(ans, 1ll*pt.tree[i].len*pt.tree[i].cnt);
		// cout<<i<<" "<<pt.tree[i].len<<" "<<pt.tree[i].link<<" "<<pt.tree[i].dep<<" "<<pt.tree[i].cnt<<"\n";
	}
	cout<<ans<<"\n";
    return 0;
}

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 456 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 456 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 0 ms 348 KB Output is correct
17 Correct 0 ms 456 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 1 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 0 ms 348 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 0 ms 452 KB Output is correct
26 Correct 0 ms 348 KB Output is correct
27 Correct 0 ms 348 KB Output is correct
28 Correct 0 ms 348 KB Output is correct
29 Correct 0 ms 348 KB Output is correct
30 Correct 0 ms 348 KB Output is correct
31 Correct 0 ms 348 KB Output is correct
32 Correct 1 ms 344 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Correct 0 ms 344 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 460 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 0 ms 460 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1628 KB Output is correct
2 Correct 1 ms 1628 KB Output is correct
3 Correct 1 ms 1628 KB Output is correct
4 Correct 1 ms 1628 KB Output is correct
5 Correct 1 ms 1628 KB Output is correct
6 Correct 1 ms 1628 KB Output is correct
7 Correct 1 ms 1624 KB Output is correct
8 Correct 1 ms 1628 KB Output is correct
9 Correct 1 ms 1628 KB Output is correct
10 Correct 1 ms 1628 KB Output is correct

Subtask #4
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 12376 KB Output is correct
2 Correct 8 ms 12380 KB Output is correct
3 Correct 6 ms 12380 KB Output is correct
4 Correct 7 ms 12512 KB Output is correct
5 Correct 6 ms 12380 KB Output is correct
6 Correct 6 ms 12380 KB Output is correct
7 Correct 7 ms 12380 KB Output is correct
8 Correct 7 ms 12380 KB Output is correct
9 Correct 7 ms 12380 KB Output is correct
10 Correct 6 ms 12380 KB Output is correct

Subtask #5
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 36832 KB Output is correct
2 Correct 23 ms 36836 KB Output is correct
3 Correct 21 ms 36904 KB Output is correct
4 Correct 21 ms 36836 KB Output is correct
5 Correct 20 ms 36832 KB Output is correct
6 Correct 21 ms 36832 KB Output is correct
7 Correct 21 ms 36836 KB Output is correct
8 Correct 19 ms 36836 KB Output is correct
9 Correct 19 ms 36832 KB Output is correct
10 Correct 20 ms 36832 KB Output is correct
11 Correct 20 ms 36836 KB Output is correct
12 Correct 18 ms 36828 KB Output is correct