#include<bits/stdc++.h>
using namespace std;
#define rep(i,N) for(i=0;i<N;i++)
#define ll long long

int main(void){
    ll N;
    string S;

    ll i,j,k;

    cin>>N;
    cin>>S;

    char now='1';
    ll ans=0;
    rep(i,N){
        if(now!=S[i]){
            ans++;
            now=S[i];
        }
    }

    cout<<ans<<endl;

    return 0;
}