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

num_valleys = 0
curr_sea_level = 0
total_steps = int(raw_input().strip())
step_map = list(str(raw_input().strip()))

for step in step_map:
    if 'U' == step:
        curr_sea_level += 1
    if 'D' == step:
        if curr_sea_level == 0:
            num_valleys += 1
        curr_sea_level -= 1

print(num_valleys)