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

n=int(raw_input())
ud=list(raw_input().strip())
count=0
value=0
for i in range (n):
    if ud[i]=='D' :
        count -= 1
    if ud[i]=='U':
        count += 1
    if count==0 and ud[i]=='U':  
        value += 1
print value