def swap(arr, l, r):
    tmp = arr[l]
    arr[l] = arr[r]
    arr[r] = tmp

def bucketDucket(ducks):
    n = len(ducks)
    C = 0
    R = 0

    for i in range(n):
        if ducks[i] == 'L':
            swap(ducks, R, i)
            swap(ducks, C, R)
            R += 1
            C += 1
        elif ducks[i] == 'C':
            swap(ducks, R, i)
            R +=1
        else:
            pass
    return ducks

print(bucketDucket(list('RRLLCC')))