# Enter your code here. Read input from STDIN. Print output to STDOUT
n=int(raw_input())
a =raw_input().strip()
b=s=0
for i in range(0,n):
    if a[i]=='D':
        b=b-1
        
    elif a[i]=='U':
        b+=1
        if b==0:
            s+=1
print s