tmp

RB-DELETE-FIXUP(T, x)
while x!=T.root and x.color==BLACK
    if x==x.p.left
        w=x.p.right
        if w.color==RED
            w.color=BLACK  //case 1
            x.p.color=RED  //case 1
            LEFT-ROTATE(T, x.p)  //case 1
            w=x.p.right  //case 1
        if w.left.color==BLACK and w.right.color==BLACK
            w.color=RED  //case 2
            x=x.p  //case 2
        else
            if w.right.color==BLACK
                w.left.color==BLACK  //case 3
                w.color=RED  //case 3
                RIGHT-ROTATE(T, w)  //case 3
                w=x.p.right  //case 3
            w.color=x.p.color  //case 4
            x.p.color=BLACK  //case 4
            w.right.color=BLACK  //case 4
            LEFT-ROTATE(T, x.p)  //case 4
            x=T.root  //case 4
    else (same as then clause with "right" and "left" exchanged)
x.color=BLACK