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

N = raw_input()
s = raw_input()

current_level = 0
valley_count = 0
for ii in s:
    if ii == 'U':
        current_level = current_level + 1
    else:
        current_level = current_level - 1
        
    if current_level == -1 and ii == 'D':
        valley_count = valley_count + 1
    #print ii
    
print valley_count