n = int(input().strip())
steps = [1 if x == 'U' else -1 for x in list(input())]

cumsum = []
current_level = 0
for s in steps:
    current_level += s
    cumsum.append(current_level)
    
num_valley = 0
valley_start = True
for ind, l in enumerate(cumsum):
    if ind == 0:
        continue
    last_l = cumsum[ind - 1]
    if l < 0 and last_l >= 0:
        valley_start = True
    elif l >= 0 and last_l < 0 and valley_start is True:
        num_valley += 1
        valley_start = False
        
print(num_valley)