#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    int sea=0; //sea level
    int n, v =0, m = 0; char c;
    cin>>n;
    for(int i=0;i<n;i++)
    {
        
        cin>>c;
        if(c == 'D'){
            --sea;
        }
        else
            ++sea;
        if(sea==0 && c=='U' ) v++;
    }
    cout<<v;
    
    return 0;
}