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

# Get out inputs
steps = raw_input()
step_sequence = raw_input()

# Initial values
altitude = 0
valleys_traveled = 0


for step in step_sequence:
    if step == 'U':
        altitude += 1
        if altitude == 0:
            valleys_traveled += 1
    else:
        altitude -= 1

print valleys_traveled