#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cmath>
#include<cstring>
#include<string>
#include<stack>
#include<queue>
#include<deque>
#include<set>
#include<vector>
#include<map>#define fst first
#define sc second
#define pb push_back
#define mem(a,b) memset(a,b,sizeof(a))
#define lson l,mid,root<<1
#define rson mid+1,r,root<<1|1
#define lc root<<1
#define rc root<<1|1
#define lowbit(x) ((x)&(-x)) using namespace std;typedef double db;
typedef long double ldb;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> PI;
typedef pair<ll,ll> PLL;const db eps = 1e-6;
const int mod = 1e9+7;
const int maxn = 2e5+100;
const int maxm = 2e6+100;
const int inf = 0x3f3f3f3f;
const db pi = acos(-1.0);char s[maxn];
int sa[maxn],rk[maxn],height[maxn];
int y[maxn],x[maxn],c[maxn];
//x是第i个元素的第一关键字
//y表示第二关键字排名为i的数，第一关键字的位置
//c是桶
int n, m;//m是字符个数
void getSa(){for(int i=1;i<=n;i++)++c[x[i]=s[i]];for(int i=2;i<=m;i++)c[i]+=c[i-1];for(int i=n;i>=1;i--)sa[c[x[i]]--]=i;for(int k=1;k<=n;k<<=1){int num = 0;for(int i=n-k+1;i<=n;i++)y[++num]=i;for(int i=1;i<=n;i++)if(sa[i]>k)y[++num]=sa[i]-k;for(int i=1;i<=m;i++)c[i]=0;for(int i=1;i<=n;i++)++c[x[i]];for(int i=2;i<=m;i++)c[i]+=c[i-1];for(int i=n;i>=1;i--)sa[c[x[y[i]]]--]=y[i],y[i]=0;swap(x,y);x[sa[1]]=1;num=1;for(int i=2;i<=n;i++){x[sa[i]]=(y[sa[i]]==y[sa[i-1]]&&y[sa[i]+k]==y[sa[i-1]+k])?num:++num;}if(num==n)break;m=num;}
}
void getHeight(){int k=0;for(int i=1; i<=n; ++i)rk[sa[i]]=i;for(int i=1; i<=n; ++i){if(rk[i]==1) continue;if(k)--k;int j=sa[rk[i]-1];while(j+k<=n&&i+k<=n&&s[i+k]==s[j+k])++k;height[rk[i]]=k;}
}
int main(){scanf("%s",s+1);n=strlen(s+1);for(int i = 1; i <= n; i++)s[i+n]=s[i];n=strlen(s+1);m=122;//ascll('z')=122
    getSa();getHeight();for(int i = 1; i <= n; i++){if(sa[i]<=n/2)printf("%c",s[sa[i]+n/2-1]);}return 0;
}
/*
JSOI07*/