Submission #916493

#	Time	Username	Problem	Language	Result	Execution time	Memory
916493		penguin133	Palindromic Partitions (CEOI17_palindromic)	C++17	15 / 100	1 ms	1116 KiB

palindromic

#include <bits/stdc++.h>
using namespace std;

#define int long long
#define pi pair<int, int>
#define pii pair<int, pi>
#define fi first
#define se second
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

string s;
const int mod = 1e18 - 1, mod2 = 1e17 + 5;
int memo[305][305];

int slv(int l, int r){
	if(l > r)return 0;
	if(l == r)return 1;
	if(memo[l][r] != -1)return memo[l][r];
	int cur = 1, cur2 = 1, cnt = 0, cnt2 = 0, cnt3 = 0, cnt4 = 0;
	int ans = 1;
	for(int i = l, j = r; i <= j; i++, j--){
		cnt = cnt * 26 + (s[i] - 'a');
		cnt3 = cnt3 * 26 + (s[i] - 'a');
		cnt2 += cur * (s[j] - 'a');
		cnt4 += cur2 * (s[j] - 'a');
		cur *= 26; cur %= mod; cur2 *= 26; cur2 %= mod2;
		cnt %= mod; cnt2 %= mod; cnt3 %= mod2; cnt4 %= mod2;
		if(cnt == cnt2 && cnt3 == cnt4)ans = max(ans, slv(i + 1, j - 1) + 2);
	}
	return memo[l][r] = ans;
}

void solve(){
	cin >> s;
	memset(memo, -1, sizeof(memo));
	cout << slv(0, (int)s.length() - 1) << '\n';
}

main(){
	ios::sync_with_stdio(0);cin.tie(0);
	int tc = 1;
	cin >> tc;
	for(int tc1=1;tc1<=tc;tc1++){
		// cout << "Case #" << tc1 << ": ";
		solve();
	}
}

Compilation message (stderr)

palindromic.cpp:42:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   42 | main(){
      | ^~~~

• Subtask 1: 15 / 15
• Subtask 2: 0 / 20
• Subtask 3: 0 / 25
• Subtask 4: 0 / 40