#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
}