#include <iostream>

using namespace std;

int main()
{
    int n, a, b;
    cin>>n>>a;
    --n;
    if (a!=1)
        cout<<"1-"<<a-1<<'\n';
    while (n)
    {
        cin>>b;
        if(b-a!=1)
            cout<<a+1<<"-"<<b-1<<'\n';
        a=b;
        --n;

    }
    if(b!=100)
        cout<<b+1<<"-100";
    return 0;
}