def main():
    num = int(raw_input())
    trip = raw_input()
    level = 0
    valleys = 0
    curr = 0
    for i in xrange(num):
        if trip[i] == 'U':
            level += 1
        elif trip[i] == 'D':
            level -= 1
        if level == 0 and trip[i] == 'U':
            valleys += 1
    print valleys
main()