n = int(input())
track = input()


def find_number_of_valleys(track):
    current_level = 0
    number_of_valleys = 0
    for move in track:
        current_level = process_move(current_level, move)
        if move == 'U' and current_level == 0:
            number_of_valleys += 1
    return number_of_valleys
    
    
def process_move(current_level, move):
    return current_level + 1 if move == 'U' else current_level -1
    
print(find_number_of_valleys(track))