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

int main() {

    int n;
    scanf("%d\n", &n);
    char newStep;
    int numOfValleys = 0;
    int prevLevel = 0, nextLevel = 0;
    
    for (int i = 1; i <= n; i++) {
        scanf("%c", &newStep);
        switch (newStep) {
            case 'U': nextLevel++; break;
            case 'D': nextLevel--; break;
        }
        if (prevLevel == 0 && nextLevel < 0){
            numOfValleys++;
        }
        prevLevel = nextLevel;
    }
    
    printf("%d", numOfValleys);
    
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */    
    return 0;
}