#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define ALL(v) v.begin(),v.end()
#define dbg(x) cerr << #x << ": " << (x) << endl;
int N;
string S;
int main() {
    cin >> N >> S;
    
    S = '#' + S + '#';
    int ans = 0;
    for (int i = 1; i < S.size(); ++i) {
        if (S[i-1] != S[i]) ++ans;
    }
    cout << ans-1 << '\n';
}