import sys

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

valley_count = 0
elevation = 0
is_mountain = False
is_valley = False
for step in steps:
    if elevation == 0:
        if step == 'U':
            elevation += 1
            is_mountain = True
        else: ## step == 'D'
            elevation -= 1
            is_valley = True
    elif elevation > 0:
        if step == 'U':
            ## is_mountain = True
            elevation += 1
        else: ## step == 'D'
            elevation -= 1
            if elevation == 0:
                is_mountain = False
    else: ## elevation < 0
        if step == 'U':
            elevation += 1
            if elevation == 0:
                is_valley = False
                valley_count += 1
        else: ## step == 'D'
            ## is_valley = True
            elevation -= 1
            
print(valley_count)