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

import sys

n = int(raw_input().strip())
steps = raw_input()
level = 0
last_level = 0
valleys = 0
in_valley = False

for step in steps:
    level = level + 1 if step == "U" else level - 1
    if level < 0:
        if in_valley == False:
            valleys = valleys + 1
        in_valley = True
        
    if level >= 0:
        in_valley = False
            
print valleys