n = int(input())
steps = input()
list = []
counter = 0
num_groups = 0
for s in steps:
    if s == 'U':
        counter+=1
    else:
        counter-=1
    if counter >=0:
        list.append('p')
    else:
        list.append('n')
for i in range(len(list)-1):
    if list[i]=='n' and list[i+1]=='p':
        num_groups+=1
print(num_groups)