Cassidoo 13/4 - generateParens

generateParens.py

# Entry function
def generateParens(n):
    return parensTree("", n, n)

# Recursive function
def parensTree(parens, openParens, closeParens):

    # Left branch recursion
    if openParens:
        leftBranch = parensTree(parens + "(", openParens - 1, closeParens)
    else:
        leftBranch = []

    # Right branch recursion
    if closeParens and openParens == closeParens:
        rightBranch = []
    elif closeParens:
        rightBranch = parensTree(parens + ")", openParens, closeParens - 1)
    else:
        rightBranch = [parens]

    return leftBranch + rightBranch