numSteps = int(raw_input().strip())
hikeSeq = raw_input().strip()
previousHeight = 0
currentHeight = 0
numValleys = 0
for step in hikeSeq:
    if step == 'D':
        previousHeight = currentHeight
        currentHeight -= 1
    if step == 'U':
        previousHeight = currentHeight
        currentHeight += 1
        if currentHeight == 0:
            if previousHeight < 0:
                numValleys += 1
print numValleys