#include <iostream>
#include <cstring>
using namespace std;
char c[100],rez[200];
int i,N,ctr;
int main()
{
    cin.getline(c,100);
    N=strlen(c);
    for(i=0;i<N;i++)
    {
        rez[ctr++]=c[i];
        if(c[i]+1==c[i+1]||c[i]-1==c[i+1])
            rez[ctr++]='-';
    }
    cout<<rez;
    return 0;
}