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

n = raw_input().strip()
s = raw_input().strip()

valley = 0
level = 0
pass_sea = 1
begin_val = 0
for index, el in enumerate(s):
    if el == 'U':
        level += 1
    else:
        level -= 1
        
    if level < 0:
        begin_val = 1
    if level == 0 and begin_val == 1:
        valley += 1
        begin_val = 0
        
print valley