#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<pii> vpii;
typedef unsigned long long llu;

#define author ayushtomar
#define rf freopen("in.txt", "r", stdin)
#define wf freopen("out.txt", "w", stdout)
#define debug(x) cerr<<#x<<" "<<x<<endl;
#define f first
#define s second
#define mp make_pair
#define pb push_back
string s1;
int A[1<<21];
int get(char a)
{
    if(a=='D')
        return -1;
    return 1;
}

    vi v;
int main()
{
    int n;
    cin>>n;
    int counts=0;
    cin>>s1;
    for(int i=1;i<=n;i++)
    {
        A[i]=A[i-1] + get(s1[i-1]);
    }
    A[n+1]=0;
    for(int i=1;i<=n+1;i++)
    {
     //   cout<<i << " "<<A[i]<<"\n";
        if(A[i]==-1 && A[i-1]==0)
            v.pb(A[i]);
        else if(A[i-1]==-1 && A[i]==0)
            v.pb(A[i]);
    }
    for(int i=1;i<v.size();i++)
    {
        if(v[i]==0 && v[i-1]==-1)
            counts++;
    }

    cout<<counts;



 return 0;
}