#include<bits/stdc++.h>

using namespace std;

const int N=1e5+;

map<string,int>mp;

string s;

int d[]={,,,,,,,,,,,};

bool isOK(string s)

{

    if(s[]!='-'||s[]!='-')return false;

    if(s[]=='-'||s[]=='-'||s[]=='-'||s[]=='-')return false;

    int a=(s[]-'')*+s[]-'';

    int b=(s[]-'')*+s[]-'';

    if(b<=||b>)return false;

    if(a<=||a>d[b-])return false;

    return true;

}

int main()

{

    cin>>s;

    int cnt=;

    string ans;

    for(int i=;i<s.size()-;i++)

    {

        if(s[i]==''&&s[i+]==''&&s[i+]==''&&''<=s[i+]&&s[i+]<='')

        {

            string s1=s.substr(i-,);

            if(isOK(s1))

            {

                string s2=s.substr(i-,);

                mp[s2]++;

                if(mp[s2]>cnt)

                {

                    cnt=mp[s2];

                    ans=s2;

                }

            }

        }

    }

    cout<<ans<<endl;

    return ;

}