#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <map>
#include <stdio.h>
#include <cmath>
using namespace std;
int dp[4005];
string s;
int n;
bool pol[4005][4005] = {false};
int path[4005][2] = {0};
int rec (int k)
{
    if (dp[k] != -1)
        return dp[k];

    if (pol[0][k])
    {
        path[k][0] = 0;
        path[k][1] = 1;
        return 1;
    }
    int mn = INT_MAX;
    for (int i = 1; i <= k; i++)
    {
        if (pol[i][k])
        {
            int res1 = rec(i - 1) + 1;
            if(res1 < mn)
            {
                mn = res1;
                path[k][0] = i;
                path[k][1] = 1;
            }
        }
        else
        {
            int res2 = rec(i - 1) + k - i + 1;
            if(res2 < mn)
            {
                mn = res2;
                path[k][0] = i;
                path[k][1] = k - i + 1;
            }
        }
    }
    if(mn == INT_MAX)
        mn = 0;
    return dp[k] = mn;
}
int main()
{
    memset(dp,255,sizeof dp);
    //freopen ("input.txt","r",stdin);
    //freopen ("output.txt","w",stdout);
    int m;
    cin >> s;
    int n = s.length();
    for (int i = 0; i < n; i++)
    {
        int l = i;
        int r = i;
        int l1 = i;
        int r1 = i + 1;
        while(l >= 0 && r < n)
            if(s[l] == s[r])
                pol[l--][r++] = true;
            else
                break;

        while(l1 >= 0 && r1 < n)
            if(s[l1] == s[r1])
                pol[l1--][r1++] = true;
            else
                break;
    }
    printf ("%d\n",rec(n - 1));
    int p = n - 1;
    vector<string> resans;
    while (p >= 0)
    {
        int t = path[p][1];
        int len = p - path[p][0] + 1;
        p = path[p][0] - 1;
        if(t == 1)
            resans.push_back(s.substr(p + 1,len));
        else
        {
            for (int i = t; i >= 1; i--)
            {
                char str[2] = {0};
                str[0]  = s[p + i];
                resans.push_back(string(str));
            }
        }
    }
    for (int i = resans.size() - 1; i >= 0; i--)
        cout << resans[i] << " ";

    return 0;
}