#include<bits/stdc++.h> using namespace std; int main() { char a[10001]; cin>>a; int m=a[0]-'0';//0 48 '0' 48 0 int i=1; while(a[i]!='\0') { if(a[i]=='.') { i++; continue; } else if(a[i]-'0'>m) { m=a[i]-'0'; } i++; } cout<<m; return 0; }