#include <fstream>

using namespace std;

int main()
{
    unsigned n,i,v[10000],aux,nrcop=0;
    ifstream fin("fazanr.in");
    ofstream fout("fazanr.out");
    fin>>n;
    for(i=1;i<=n;i++)
    fin>>v[i];
    for(i=1;i<n;i++)
    {
        aux=v[i+1];
        while(aux>=10)
        aux=aux/10;
        if(v[i]%10!=aux)
        nrcop++;
    }
        fout<<nrcop;
    fin.close();
    fout.close();
    return 0;
}