# Read info
numElements = int(input().strip())
steps = input()
altitude = 0
numValleys = 0
valleyFlag = 0

# Algorithm 
for step in steps:
    if step == 'D':
        if altitude == 0:
            valleyFlag = 1
        altitude = altitude - 1
    elif step == 'U':
        if altitude == -1:
            valleyFlag = 0
            numValleys = numValleys + 1
        altitude = altitude + 1

print(int(numValleys))