#1315_字符串编码

//
// Created by mingy on 2016-04-02.
//
#include <iostream>
#include <vector>
#include <queue>
 
using namespace std;
 
string s;
vector<char> new_s;
string table[256];
 
struct Node {
    int weight;
    char ch;
    Node *left;
    Node *right;
    Node():left(NULL), right(NULL), ch('0'), weight(0){}
};
 
struct cmp_each_char{
    bool operator()(Node *a, Node *b){
        return a->weight > b->weight;
    }
};
priority_queue <Node*, vector<Node*>, cmp_each_char> pq_Nodes;
 
bool isNewCh(char ch) {
    for (int i = 0; i < new_s.size(); ++i)
        if (ch == new_s[i])
            return false;
    return true;
}
 
void show(Node* x){
    if(x->left == NULL && x->right == NULL){
        cout <<x->ch << "\t" <<x->weight<< endl;
        return;
    }
    show(x->left);
    show(x->right);
}
 
void buildTable(Node* x, string st){
    if(x->left == NULL && x->right == NULL){
        table[x->ch] = st;
        return;
    }
    buildTable(x->left, st + "1");
    buildTable(x->right, st + "0");
}
 
int main() {
    cin >> s;
    for (int i = 0; i < s.length(); ++i)
        if (isNewCh(s[i]))
            new_s.push_back(s[i]);
 
    vector <Node> each_char;
 
    for (int i = 0; i < new_s.size(); ++i) {
        Node * new_char = new Node();
        new_char->ch = new_s[i];
        each_char.push_back(*new_char);
    }
 
    for (int i = 0; i < new_s.size(); ++i)
        for (int j = 0; j < s.size(); ++j)
            if (s[j] == new_s[i])
                each_char[i].weight++;
 
    for (int i = 0; i < new_s.size(); ++i)
        pq_Nodes.push(&each_char[i]);
 
    while(pq_Nodes.size() > 1){
        Node * a= pq_Nodes.top();
        pq_Nodes.pop();
        Node * b = pq_Nodes.top();
        pq_Nodes.pop();
        Node * parent = new Node();
        parent->weight = b->weight + a->weight;
        parent->left = b;
        parent->right = a;
        pq_Nodes.push(parent);
    }
 
    buildTable(pq_Nodes.top(), "");
 
    int count = 0;
    for (int i = 0; i < s.size(); ++i)
        count += table[s[i]].size();
 
    if (new_s.size() == 1)
        count = s.size();
    cout << count << endl;
    return 0;
}
 
/**************************************************************
    Problem: 1315
    User: 22920142203903
    Language: C++
    Result: Accepted
    Time:74 ms
    Memory:1772 kb
****************************************************************/