nand2tetris/projects/01/Or8Way.hdl

// This file is part of www.nand2tetris.org
// and the book "The Elements of Computing Systems"
// by Nisan and Schocken, MIT Press.
// File name: projects/01/Or8Way.hdl

/**
 * 8-way Or:
 * out = (in[0] or in[1] or ... or in[7])
 */

// COST = 7x3 = 21 NAND Gates

CHIP Or8Way {
    IN in[8];
    OUT out;

    PARTS:
    Or(a=in[0], b=in[1], out=p);
    Or(a=in[2], b=in[3], out=q);
    Or(a=in[4], b=in[5], out=r);
    Or(a=in[6], b=in[7], out=s);

    Or(a=p, b=q, out=x);
    Or(a=r, b=s, out=y);

    Or(a=x, b=y, out=out);
}