//第一题



	
	

		 #include <stdio.h>
#include<iostream>
#include<ctime>
#include<cstdlib>
#include<cmath>
using namespace std;
int main()
{
    string s;
    int ans(0),x;
    cin>>s;
    for(int i=0;i<s.length();i++)
    {
        if(isalpha(s[i])==0)
        {
           x=s[i]-'0';
           while(isalpha(s[++i])==0 && i<s.length())
                x=x*10+s[i]-'0';
           if(x>ans)ans=x;
        }
    }
    cout<<ans;
  return 0;
} 
	




	



	//第二题



	
	

		 #include<iostream>
#include<string>
#include<algorithm>
using namespace std;
int z[10];
int main()
{
    int n;
    cin>>n;
    for(int i=0;i<n;i++){
        cin>>z[i];
    }
    for(int i=0;i<n;){
        if(z[i+1]-1==z[i]){
            int cc=i;
            int num=0;
            while(z[i+1]-1==z[i]){
                num++;
                i++;
            }
            if(num>=2){
                if(cc!=0){
                    cout<<',';
            
                }
                cout<<z[cc]<<'-'<<z[i];
                i++;    
            }
            else {
                i=cc;
                if(cc!=0){
                    cout<<',';
                }
                cout<<z[i];
                i++;
                
            }
            
        }
        else {
            if(i!=0){
                    cout<<',';
                }
                cout<<z[i];
                i++;
        }
    }
    return 0;
} 
	

	

		
	

	

		
	
//第三题



	
	

		 #include <stdio.h>
#include<iostream>
#include<ctime>
#include<cstdlib>
#include<cmath>
#include<algorithm>
using namespace std;
int main()
{
    int n;
    int a[110];
    cin>>n;
    for(int i=0;i<n;i++)
        cin>>a[i];
    for(int i=0;i<n;i++)
            cout<<a[i];
    cout<<endl;
    while(next_permutation(a,a+n))
    {
        for(int i=0;i<n;i++)
            cout<<a[i];
        cout<<endl;
    }
  return 0;
}