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

int main() {

    /* Enter your code here. Read input from STDIN. Print output to STDOUT */    

	int n, dcnt = 0, ucnt = 0, vcnt = 0;
	char ch;
	int vstart = 0;

	scanf("%d\n", &n);

	while(EOF!=(ch=fgetc(stdin)) && ch != '\n'){
		if (ch == 'D') 
			dcnt++;
		else if (ch == 'U')
			ucnt++;

		if (dcnt > ucnt && !vstart) {
			vstart = 1;
		} else if (dcnt == ucnt && vstart) {
			vcnt++;
			vstart = 0;
		}
	}

	printf ("%d\n", vcnt);

    return 0;
}