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

n=raw_input()
s=raw_input()

h=0
v=False
res=0
for i in s:
    if i=='U':
        h+=1
    else:
        h-=1
    if h<0 and v==False:
        res+=1
        v=True
    elif h>=0 and v==True:
        v=False
    
    
    
print res