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

char s[1000005];

int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */  
    int l;
    scanf("%d", &l);
    
    scanf("%s", s);
    
    int h = 0;
    int cnt = 0;
    
    for(int i = 0; i < l; i++){
        if(s[i] == 'U'){
            h++;
        }
        else{
            if(h == 0)cnt++;
            h--;
        }
    }
    
    printf("%d", cnt);
    
    return 0;
}