#include <bits/stdc++.h>

#define boAshraf ios_base::sync_with_stdio(false); cin.tie(NULL);
#define ll long long
#define sz(s) (int)(s).size()
#define all(s) (s).begin(),(s).end()
using namespace std;

void File();
void sol();
const int N=5001;
string s;
int n;
int common[N][N];
int dp[N][N];
int get(int i,int j){
    if(j==n)return 0;
    int &ret=common[i][j];
    if(~ret)return ret;
    ret=0;
    if(s[i]==s[j])ret=1+get(i+1,j+1);
    return ret;
}
int rec(int i,int last){
    if(i>n)return -1e9;
    if(i==n)return 0;
    int &ret=dp[i][last];
    if(~ret)return ret;
    ret=-1e9;
    if(last!=0) {
        ret = max(ret, rec(i + 1, last + 1));
        int c=min(last+1,get(i-last,i));
        int i1=i-last+c,i2=i+c;
        if(c>=last)ret=max(ret,1+rec(i+last+1,last+1));
        else if(s[i1]<s[i2])ret=max(ret,1+rec(i+c+1,c+1));
    }else{
        ret=rec(i+1,1)+1;
    }
    return ret;
}
void build(int i,int last){
    if(i==n) {
        cout<<s.substr(i-last,last)<<'\n';
        return;
    }
    int &ret=dp[i][last];
    if(last!=0) {
        if(ret==rec(i+1,last+1)){
            return build(i+1,last+1);
        }
        int c=min(last+1,get(i-last,i));
        int i1=i-last+c,i2=i+c;
        if(c>=last && ret==1+rec(i+last+1,last+1)) {
            cout<<s.substr(i-last,last)<<'\n';
            return build(i+last+1,last+1);
        }
        else if(s[i1]<s[i2] && ret==1+rec(i+c+1,c+1)){
            cout<<s.substr(i-last,last)<<'\n';
            return build(i+c+1,c+1);
        }
        assert(0);
    }else{
        return build(i+1,1);
    }
}
int main() {
    boAshraf
    File();
    int t = 1;
//    cin >> t;
    while (t--) {
        sol();
    }
    return 0;
}

void sol() {
    cin>>s;
    n=sz(s);
    memset(common,-1,sizeof common);
    memset(dp,-1,sizeof dp);
    cout<<rec(0,0)<<'\n';
    build(0,0);
}

void File() {
#ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
}