# Enter your code here. Read input from STDIN. Print output to STDOUT
n=int(raw_input().strip())
walk=raw_input().strip()
alt=0
valley=False
count=0
for i in xrange(n):
    if walk[i]=='U':
        alt=alt+1
    else:
        alt=alt-1
    if alt<0:
        valley=True
        continue
    if alt==0 and valley:
        count=count+1
    else:
        valley=False
print count