#!/bin/python

import sys


n = int(raw_input().strip())
directions = raw_input().strip()

sea_level = 0

valleys_amount = 0


for step in directions:
    if step == 'U':
        sea_level += 1

    elif step == 'D':
        if sea_level == 0:
            valleys_amount += 1
        sea_level -= 1

print valleys_amount