oj.uz

답안 #42861

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
42861 2018-03-05T16:44:51 Z ToMoClone 회문 (APIO14_palindrome) C++14
0 / 100
 653 ms 29556 KB 
/*input
www
a
aba
abacaba
acaba
ba
bacaba
caba
*/
#include <bits/stdc++.h>
using namespace std;

const int N = 300005;

namespace SuffixArray {
	int pos[N], sa[N], tmp[N], lcp[N], gap, n;
	string s;

	bool SuffixCmp(int i, int j) {
		if(pos[i] != pos[j]) return pos[i] < pos[j];
		i += gap, j += gap;
		return (i < n && j < n) ? (pos[i] < pos[j]) : (i > j);
	}

	void buildSA(string x) {
		n = (int)x.size(), s = x;
		for(int i = 0; i < n; ++i) pos[i] = s[i], sa[i] = i;
		for(gap = 1; ; gap *= 2) {
			sort(sa, sa + n, SuffixCmp);
			for(int i = 1; i < n; ++i) tmp[i] = tmp[i - 1] + SuffixCmp(sa[i - 1], sa[i]);
			for(int i = 0; i < n; ++i) pos[sa[i]] = tmp[i];
			if(tmp[n - 1] == n - 1) break;
		}
	}

	void Kasai() {
		for(int i = 0, k = 0; i < n; ++i) if(pos[i] != n - 1) {
			for(int j = sa[pos[i] + 1]; s[i + k] == s[j + k]; ++k);
			lcp[pos[i]] = k; if(k != 0) --k;
		}
	}
}

namespace MaxRange {
	int lef[N], rig[N], mn[18][N];

	int get(int l, int r) {
		int dist = log2(r - l + 1);
		return min(mn[dist][l], mn[dist][r - (1 << dist) + 1]);
	}

	long long Solve(vector<int> &x, vector<int> &val) {
		int n = x.size();

		for(int i = 1; i < n - 1; ++i)
			mn[0][i] = x[i];

		for(int i = 1; (1 << i) < n - 1; ++i)
			for(int j = 1; j + (1 << i) < n; ++j)
				mn[i][j] = min(mn[i - 1][j], mn[i - 1][j + (1 << (i - 1))]);

		long long Ans = 0;
		for(int i = 1; i < n - 1; ++i) {
			int le = 1, ri = i - 1, l, r;
			
			if(i == 1) l = 1;
			else if(x[i - 1] < val[i]) l = i;
			else {
				while(le < ri) {
					int mid = (le + ri) >> 1;
					if(get(mid, i - 1) < val[i]) le = mid + 1;
						else ri = mid;
				}
				l = le;
			}

			if(i == n - 2) r = i;
			else if(x[i] < val[i]) r = i;
			else  {
				le = i, ri = n - 2;
				while(le < ri) {
					int mid = (le + ri + 1) >> 1;
					if(get(i, mid) < val[i]) ri = mid - 1;
						else le = mid;
				}
				r = le + 1;
			}
			Ans = max(Ans, 1ll * (r - l + 1) * val[i]);
		}
		return Ans;
	}
}

int main(){
	iostream::sync_with_stdio(false); cin.tie(0);
	string s; cin >> s;

	int n = (int)s.size();
	SuffixArray::buildSA(s);
	SuffixArray::Kasai();

	vector<int> v, val;
	v.reserve(n + 2), val.reserve(n + 2);
	v.emplace_back(- 1), val.emplace_back(0);

	for(int i = 0; i < n; ++i) {
		v.emplace_back(SuffixArray::lcp[i]);
		val.emplace_back(n - SuffixArray::sa[i]);
	}
	v.emplace_back(- 1), val.emplace_back(0);

	printf("%lld\n", MaxRange::Solve(v, val));
	// cerr << fixed << setprecision(6) << (double)clock() / CLOCKS_PER_SEC << endl;
}

Subtask #1
0 / 8.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 376 KB Output is correct
2 Correct 1 ms 484 KB Output is correct
3 Correct 1 ms 484 KB Output is correct
4 Correct 2 ms 488 KB Output is correct
5 Incorrect 1 ms 708 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #2
0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 3 ms 960 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 24.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 14 ms 1584 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 26.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 201 ms 9660 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 27.0

# 결과 실행 시간 메모리 Grader output
1 Correct 653 ms 29228 KB Output is correct
2 Incorrect 482 ms 29556 KB Output isn't correct
3 Halted 0 ms 0 KB -