266A - Stones on the Table

#include<bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    string s;

    cin>>s;

    int count=0;

    for(int i=0;i<n;i++)

    {

        if(s[i]==s[i+1])

        {

            count++;

        }

    }

    cout<<count<<endl;

}