n = int(input())
steps = input()

sea_level = 0
last_sea_level = 0
is_in_valley = False
valleys = 0

for x in range(len(steps)):
    last_sea_level = sea_level
    if steps[x] == "D":
        sea_level -= 1
    else:
        sea_level += 1
    if sea_level == 0 and last_sea_level == -1:
        valleys += 1
    
print(valleys)