Submission #1157289

#	Time	Username	Problem	Language	Result	Execution time	Memory
1157289		SmuggingSpun	Palindromic Partitions (CEOI17_palindromic)	C++20	100 / 100	91 ms	11024 KiB

palindromic

#include<bits/stdc++.h>
#define taskname "B"
using namespace std;
typedef long long ll;
const int mod = 2e9 + 33;
const int base = 397;
const int lim = 1e6 + 5;
int hash_value[lim], pw_base[lim];
int get(int l, int r){
	return (ll(hash_value[r]) - 1LL * hash_value[l - 1] * pw_base[r - l + 1] + 1LL * mod * mod) % mod;
}
int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	if(fopen(taskname".inp", "r")){
		freopen(taskname".inp", "r", stdin);
	}
	for(int i = pw_base[0] = 1; i < lim; i++){
		pw_base[i] = 1LL * pw_base[i - 1] * base % mod;
	}
	int _t;
	cin >> _t;
	for(int _ = hash_value[0] = 0; _ < _t; _++){
		string s;
		cin >> s;
		int n = s.size(), ans = 0;
		for(int i = 1; i <= n; i++){
			hash_value[i] = (1LL * hash_value[i - 1] * base + s[i - 1]) % mod;
		}	
		for(int i = 1; i <= ((n + 1) >> 1); i++){
			bool have = false;
			for(int j = i; j <= (n >> 1); j++){
				if(get(i, j) == get(n - j + 1, n - i + 1)){
					have = true;
					i = j;
					ans += 2;
					break;
				}
			}
			if(!have){
				ans++;
				break;
			}
		}
		cout << ans << "\n";
	}
}

Compilation message (stderr)

palindromic.cpp: In function 'int main()':
palindromic.cpp:15:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |                 freopen(taskname".inp", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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