#include <bits/stdc++.h>

using namespace std;
int x,c,i,v[100000000];
int main()
{
    for(int i=0;i<=10000000;i++){
        v[i]=-1;
    }
    cin>>x;i=0
    ;
    while(x){
        v[i]=x%10;
        i+=2;
        x/=10;
    }
    c=i;
    for(int i=c-2;i>=0;i--)
        if(v[i] == -1)
            cout<<"-";
        else
            cout<<v[i];
    return 0;
}