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

N = int(raw_input().strip())

path = raw_input()

level = 0

poss_valley = False
valleys = 0

for step in path:
    if step == 'U':
        direction = 1
    else:
        direction = -1
        
    level += direction
        
    if poss_valley:
        if level == 0:
            valleys += 1
            poss_valley = False
    else:
        if level == -1:
            poss_valley = True
            
print valleys