#include <stdio.h>
#include <stdbool.h>
#include <string.h>

bool isPalindrome[2500][2500];
char str[2501];
int dp[2500];

int main() {
    scanf("%s", str);
    int length = strlen(str);

    isPalindrome[0][0] = true;
    for(int i=1; i<length; i++) {
        isPalindrome[i][i] = true;
        
        if(str[i-1] == str[i]) {
            isPalindrome[i-1][i] = true;
        }
    }

    for(int len = 3; len <= length; len++) {
        for(int start = 0; start <= length - len; start++) {
            int end = start + len - 1;
            
            if(str[start] == str[end] && isPalindrome[start+1][end-1]) {
                isPalindrome[start][end] = true;
            }
        }
    }

    for(int i=0; i<length; i++) dp[i] = length;

    for(int end=0; end<length; end++) {
        for(int start=0; start <=end; start++) {
            if(isPalindrome[start][end]) {
                if(start == 0) dp[end] = 1;
                else dp[end] = (dp[end] < dp[start-1] + 1) ? dp[end] : dp[start-1] + 1;
            }
        }
    }

    printf("%d\n", dp[length-1]);

    return 0;
}