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

n = int(raw_input().strip())
l = raw_input()
ln = []
for i in l:
    if i == 'U':
        ln.append(1)
    else:
        ln.append(-1)
        
count = 0
x = 0
for i in ln:
    x += i
    if x == -1 and i == -1:
        count += 1
print count