num = int(input())
valley = list(input())
count = 0
deep = [0, 1]
for i in range(num):
    if valley[i].lower() == 'd':
        count -= 1
    elif valley[i].lower() == 'u':
        count += 1
    if count < 0 and deep[1] == 1:
        deep[0] += 1
    if count >= 0:
        deep[1] = 1
    else:
        deep[1] = 0
        
print(deep[0])