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

int main() {

    int N , count = 0 ,flag = 0 , valley = 0 ;
    char steps[1000000];
    scanf("%d",&N);
    
    //for(int i = 0 ; i < N ; i++)
        scanf("%s",steps);
    
    for(int i = 0 ; i < N ; i++){
        if(steps[i] == 'U')
            count++;
        else if(steps[i] == 'D')
            count--;
        
        if(count < 0)
            flag = 1 ;
        if(count == 0 && flag == 1){
            valley++;
            flag = 0;
        }
    }
    printf("%d",valley);
    return 0;
}