#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>

int main() {
    int elevation = 0;
    int valleyCount = 0;
    
    int n;
    scanf("%d", &n);
    getchar();
    
    char step;
    for(int i = 0; i < n; i++) {
        scanf("%c", &step); 
        if(step == 'U') {
            if(elevation == -1) {
                valleyCount++;
            }
            elevation++;
        } else {
            elevation--;
        }
        
    }
        
    printf("%d", valleyCount);
    return 0;
}