#include<bits/stdc++.h>
using namespace std;
int main(){
string s;
cin>>s;
int cnt=0;
for(int i=0;i<s.size();i++){
if(s[i]>='A' && s[i]<='Z' && s[i+1]>='A' &&s[i+1]<='Z') cnt++;
if(s[i]>='a' && s[i]<='z' && s[i+1]>='a' &&s[i+1]<='z') cnt++;
}
cout<<cnt;
return 0;
}
