Submission #622671

#	Time	Username	Problem	Language	Result	Execution time	Memory
622671		enter_hedgehog_poly	Palindromic Partitions (CEOI17_palindromic)	C++11	100 / 100	57 ms	11008 KiB

palindromic

//Palindromiczny podział
#include <bits/stdc++.h>

using namespace std;

char buff[1000010];

typedef uint64_t ll;
const ll P = 31;
const ll MOD_N = 31;
const ll MOD = ((ll) 1 << MOD_N) - 1;

inline ll FMOD(ll x) { return ((x) >> MOD_N) + ((x) & MOD); }

int main() {
	int t;
	scanf("%d", &t);
	while(t--) {
		scanf("%s", buff + 1);
		int n = strlen(buff + 1);

		ll left = 0, right = 0, exp = 1;
		int lp = 1, res = 0;

		for(int i = 1; i <= n / 2; i++) {
			left = FMOD(left + (buff[i] - 'a' + 1) * exp);
			exp = FMOD(exp * P);
			right = FMOD(right * P + (buff[n + 1 - i] - 'a' + 1));
			if(left == right) {
				exp = 1;
				left = right = 0;
				res += 2;
				lp = i + 1;
			}
		}

		if(lp != (n / 2) + 1 || (n & 1)) res++;

		printf("%d\n", res);
	}
	return 0;
}

Compilation message (stderr)

palindromic.cpp: In function 'int main()':
palindromic.cpp:17:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 |  scanf("%d", &t);
      |  ~~~~~^~~~~~~~~~
palindromic.cpp:19:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   19 |   scanf("%s", buff + 1);
      |   ~~~~~^~~~~~~~~~~~~~~~

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