def countingValleys(steps, path):
    altitude = 0
    nValleys = 0
    for i in range(steps):
        step = path[i]
        if step == "U":
            altitude += 1
        else:
            altitude -=1
        if altitude == 0:
            if step == "U":
                nValleys += 1
    return nValleys