Submission #104483

#	Time	Username	Problem	Language	Result	Execution time	Memory
104483		E869120	Palindromes (APIO14_palindrome)	C++14	23 / 100	967 ms	1996 KiB

palindrome

#include <iostream>
#include <string>
#include <map>
#include <algorithm>
#include <vector>
using namespace std;

long long L[10009]; string S;
pair<long long, int> L1[10009]; int cnt1, cnt2;

bool ispalindrome(string V) {
	for (int i = 0; i < V.size(); i++) {
		if (V[i] != V[V.size() - 1 - i]) return false;
	}
	return true;
}

int main() {
	cin >> S;
	for (int i = 0; i < S.size(); i++) L[i] = (S[i] - 'a') + 1;

	long long maxn = 0;

	// 真ん中が決まっている場合
	cnt1 = 0;
	for (int t = 1; t <= 26; t++) {
		for (int i = 0; i < S.size(); i++) { if (L[i] == t) { L1[cnt1] = make_pair(L[i], i); cnt1++; } }
	}

	for (int i = 1; i <= S.size(); i += 2) {
		int t1 = 0;
		for (int j = 0; j < cnt1; j++) {
			t1++;
			maxn = max(maxn, 1LL * t1 * i);
			if (L1[j].first != L1[j + 1].first) t1 = 0;
		}
		vector<pair<long long, int>>G[28];
		for (int j = 0; j < cnt1; j++) {
			int pos1 = L1[j].second - (i / 2) - 1, pos2 = L1[j].second + (i / 2) + 1;
			if (pos1 >= 0 && pos2 < S.size() && L[pos1] == L[pos2]) G[L[pos1]].push_back(make_pair(311LL * L1[j].first + L[pos1], L1[j].second));
		}
		cnt1 = 0;
		for (int j = 1; j <= 26; j++) {
			for (int k = 0; k < G[j].size(); k++) {
				L1[cnt1] = G[j][k]; cnt1++;
			}
		}
	}

	// 真ん中が決まっていない場合
	cnt1 = 0;
	for (int t = 1; t <= 26; t++) {
		for (int i = 0; i < S.size() - 1; i++) { if (L[i] == L[i + 1] && L[i] == t) { L1[cnt1] = make_pair(L[i], i); cnt1++; } }
	}

	for (int i = 2; i <= S.size(); i += 2) {
		int t1 = 0;
		for (int j = 0; j < cnt1; j++) {
			t1++;
			maxn = max(maxn, 1LL * t1 * i);
			if (L1[j].first != L1[j + 1].first) t1 = 0;
		}
		vector<pair<long long, int>>G[28];
		for (int j = 0; j < cnt1; j++) {
			int pos1 = L1[j].second - (i / 2), pos2 = L1[j].second + (i / 2) + 1;
			if (pos1 >= 0 && pos2 < S.size() && L[pos1] == L[pos2]) G[L[pos1]].push_back(make_pair(311LL * L1[j].first + L[pos1], L1[j].second));
		}
		cnt1 = 0;
		for (int j = 1; j <= 26; j++) {
			for (int k = 0; k < G[j].size(); k++) {
				L1[cnt1] = G[j][k]; cnt1++;
			}
		}
	}

	cout << maxn << endl;
	return 0;
}

Compilation message (stderr)

palindrome.cpp: In function 'bool ispalindrome(std::__cxx11::string)':
palindrome.cpp:12:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < V.size(); i++) {
                  ~~^~~~~~~~~~
palindrome.cpp: In function 'int main()':
palindrome.cpp:20:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < S.size(); i++) L[i] = (S[i] - 'a') + 1;
                  ~~^~~~~~~~~~
palindrome.cpp:27:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 0; i < S.size(); i++) { if (L[i] == t) { L1[cnt1] = make_pair(L[i], i); cnt1++; } }
                   ~~^~~~~~~~~~
palindrome.cpp:30:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 1; i <= S.size(); i += 2) {
                  ~~^~~~~~~~~~~
palindrome.cpp:40:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if (pos1 >= 0 && pos2 < S.size() && L[pos1] == L[pos2]) G[L[pos1]].push_back(make_pair(311LL * L1[j].first + L[pos1], L1[j].second));
                     ~~~~~^~~~~~~~~~
palindrome.cpp:44:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int k = 0; k < G[j].size(); k++) {
                    ~~^~~~~~~~~~~~~
palindrome.cpp:53:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 0; i < S.size() - 1; i++) { if (L[i] == L[i + 1] && L[i] == t) { L1[cnt1] = make_pair(L[i], i); cnt1++; } }
                   ~~^~~~~~~~~~~~~~
palindrome.cpp:56:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 2; i <= S.size(); i += 2) {
                  ~~^~~~~~~~~~~
palindrome.cpp:66:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if (pos1 >= 0 && pos2 < S.size() && L[pos1] == L[pos2]) G[L[pos1]].push_back(make_pair(311LL * L1[j].first + L[pos1], L1[j].second));
                     ~~~~~^~~~~~~~~~
palindrome.cpp:70:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int k = 0; k < G[j].size(); k++) {
                    ~~^~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 15 / 15
• Subtask 3: 0 / 24
• Subtask 4: 0 / 26
• Subtask 5: 0 / 27