#include <iostream>
#include <string>
using namespace std;
int main() {
string s;
cin>>s;
if (s[0]>'Z' && s[0]<'A'){
cout<<"No";
return 0;
}
else{
int p=1;
for (int i=1; i<s.size(); i++){
if (s[i]<='z' && s[i]>='a'){
p++;
if (p==5){
cout<<"No";
return 0;
}
}
if (s[i]<='Z' && s[i]>='A'){
if (p<2){
cout<<"No";
return 0;
}
p=1;
}
}
cout<<"Yes";
return 0;
}
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