n=int(input())
arr=[x for x in input()]
c=0
x=0
flag=0
for i in range(n):
    if(arr[i]=='U'):
        c=c+1
    else:
        c=c-1
    if(c<0 and flag==0):
        flag=1
        x=x+1
    elif(c>=0):
        flag=0
print(x)