count = int(raw_input())
hike = raw_input()
level = 0
valleys = 0
for i in xrange(count):
    prev = level
    if hike[i] == 'U':
        level += 1
    if hike[i] == 'D':
        level += -1
    if prev >= 0 and level < 0:
        valleys += 1
print valleys