#!/bin/python3

import sys


n = int(input().strip())
steps = list(input().strip())

valleys = 0
elevation = 0

for step in steps:
    prev_elevation = elevation
    
    if step == 'U':
        elevation += 1
    else:
        elevation -= 1
        
    if prev_elevation >= 0 and elevation < 0:
        valleys += 1
        
print(valleys)