import sys
import re

input = []

for line in sys.stdin:
    input.append(line)

list = []
for l in input[1]:
    if l =='U':
        list.append(1)
    else:
        list.append(-1)
        
v = 0
h = 0
for i in list:
    h_old = h
    h += i
    if h == 0 and h_old < 0:
        v += 1
print v