#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

vector<vector<int>> dp;
vector<vector<int>> pos;
vector<ll> p;
vector<ll> h;

string s;

const ll mod = 1e9 + 7;

int solve(int l, int r){
    int a = s[r] - 'a';
    int left = 0;
    int right = pos[a].size();
    while(right - left > 1){
        int m = (left + right) / 2;
        if(pos[a][m] >= l){
            right = m;
        }
        else{
            left = m;
        }
    }
    if(pos[a][left] >= l)
        right = left;
    for(int i = right; i < pos[a].size(); ++i){
        if(pos[a][i] >= l && pos[a][i] < (l + r + 1) / 2){
            int len = pos[a][i] - l + 1;
            ll h1 = h[l + len - 1] + mod;
            if(l - 1 >= 0)
                h1 -= h[l - 1];
            ll h2 = h[r] + mod - h[r - len];
            if((h1 * p[r - len + 1 - l]) % mod == h2 % mod)
                return(len);
        }
    }
    return 0;
}


int f(int l, int r){
    if(l == r){
        return 1;
    }
    if(dp[l][r] != 0){
        return(dp[l][r]);
    }
    int x = solve(l, r);
    if(x == 0){
        dp[l][r] = r - l + 1;
    }
    else{
        dp[l][r] = min(f(l + x, r), f(l, r - x));
    }
    return(dp[l][r]);
}

int main() {
    cin >> s;
    if(s.size() == 1){
        cout << 1 << endl;
        return 0;
    }
    int n = s.size();
    h.resize(n);
    p.resize(n);
    pos.resize(26, vector<int>());
    for(int i = 0; i < n; ++i){
        pos[s[i] - 'a'].push_back(i);
    }
    h[0] = (s[0] - 'a' + 1);
    p[0] = 1 * 1LL;
    for(int i = 1; i < n; ++i){
        p[i] = p[i - 1] * 29 * 1LL;
        p[i] %= mod;
    }
    for(int i = 1; i < n; ++i){
        h[i] = h[i - 1] + (s[i] - 'a' + 1) * p[i] * 1LL;
        h[i] %= mod;
    }
    dp.resize(s.size(), vector<int>(s.size()));
    f(0, s.size() - 1);
    cout << dp[0][s.size() - 1] << "\n";
}