# Enter your code here. Read input from STDIN. Print output to STDOUT
n = int(input())
s = raw_input()
lvl = 0
cnt = 0
for i in s:
    if lvl == 0 and i == 'D':
        cnt += 1
        lvl -= 1
    elif i == 'U':
        lvl += 1
    else:
        lvl -= 1
print cnt