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

a = raw_input()
steps = raw_input()

count_v = 0
current_level = 0
below = False
above = False

for s in steps:
    if s == 'U':
        current_level += 1
    else:
        current_level -= 1
    if current_level < 0:
        below = True
    if current_level > 0:
        above = True
    if below and current_level== 0:
        count_v += 1
        below = False

print count_v