#!/bin/python3

import sys

n = int(input().strip())
steps = input().strip()
valleys = 0
height = 0
lastheight = 0
for step in steps:
     if (step == 'U'):
        height += 1
     else:
        height -=1
     if (height == -1 and lastheight == 0):
        valleys += 1
     lastheight = height
print (valleys)