#include    <iostream>
#include    <cstring>

using namespace std;

int main()
{
    char text[101];
    cin.getline(text,101);

    int cifraMax = -1;
    int avemCifre = 0;

    int nr = 0;
    char cMax = NULL;
    char *cuvant = strtok(text, " ");
    while(cuvant != NULL)
    {
        if(cuvant[0] >= '0' && cuvant[0] <= '9')
        {
            char c = cuvant[0];
            if(c > cMax)
            {
                nr = 0;
                cMax = c;
                for(int i = 0; i < strlen(cuvant); i++)
                    nr = nr * 10 + cuvant[i] - '0';
            }
            avemCifre = 1;
        }
        cuvant = strtok(NULL, " ");
    }
    if(avemCifre == 1)
        cout << nr;
    else
        cout << "nu exista";
    return 0;
}