union-find/contiguous

import {identity} from '../fundamentals/index.js';

export const union = (p, a, b) => {
    p[find(p, b)] = find(p, a);

    return a;
};

export const find = (p, x) => {
    while (x !== p[x]) x = p[x];

    return x;
};

export function Universe(n, List = Array) {
    this.p = identity(n, List);
}

Universe.prototype.union = function (a, b) {
    return union(this.p, a, b);
};

Universe.prototype.find = function (x) {
    return find(this.p, x);
};