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function area(current: Interval): bigint {    return BigInt(current.right - current.left) *        BigInt(current.up - current.down);}function rectangleArea(rectangles: number[][]): number {    const left = Math.min(...rectangles.map((a) => a[0]));    const down = Math.min(...rectangles.map((a) => a[1]));    const right = Math.max(...rectangles.map((a) => a[2]));    const up = Math.max(...rectangles.map((a) => a[3]));
    const total = { left, right, down, up };    const root = new SegmentNode(total);
    for (const [left, down, right, up] of rectangles) {        change(root, { left, right, down, up }, 1n);    }
    return Number(root.value % BigInt(10 ** 9 + 7));}function change(    node: SegmentNode,    target: Interval,    value: bigint,) {    const current = node.interval;    if (        target.up < current.down ||        target.right < current.left ||        target.down > current.up ||        target.left > current.right    ) {        return;    }
    if (        contains(target, current)    ) {        if (node.children.length === 0) {            node.value = value *                area(current);
            return;        }    } else {        if (node.children.length === 0) {            const midx = [target.left, target.right].filter((a) =>                current.left < a && current.right > a            )[0] ?? current.right;            const midy = [target.down, target.up].filter((a) =>                current.down < a && current.up > a            )[0] ?? current.up;            const subinterval = TwoDSplit(current, midx, midy);
            if (subinterval.length) {                node.children = subinterval.map(                    (c) =>                        new SegmentNode(                            c,                            area(c) *                                BigInt(node.value > 0),                        ),                );            }        }    }    if (node.children.length) {        for (const child of node.children) {            change(child, target, value);        }
        node.value = node.children.length            ? node.children.reduce((a, n) => a + n.value, 0n)            : node.value;
        if (            node.value === value *                    area(current) || node.value === 0n        ) {            node.children.length = 0;        }    }}export function contains(target: Interval, current: Interval): boolean {    return target.left <= current.left &&        target.down <= current.down &&        target.right >= current.right &&        target.up >= current.up;}
export function TwoDSplit(    current: Interval,    midx: number,    midy: number,): Interval[] {    const { left, right, up, down } = current;
    if (left > right || down > up) return [];
    if ((right - left) * (up - down) <= 1) return [];    const mx = midx;
    const my = midy;
    const lr = [        { left: left, right: mx },        { left: mx, right: right },    ];    const du = [        { down: down, up: my },        { down: my, up: up },    ];    const result = lr        .map(({ left, right }) =>            du.map(({ up, down }) => ({ left, right, down, up }))        )        .flat();    return result.filter(        ({ left, right, up, down }) =>            left <= right && down <= up && (right - left) * (up - down) &&            !(left === current.left && down === current.down &&                up === current.up && right === current.right),    );}export class SegmentNode {    constructor(        public interval: Interval = new Interval(),        public value: bigint = 0n,        public children: SegmentNode[] = [],    ) {}}export class Interval {    constructor(        public left = 0,        public right = 0,        public down = 0,        public up = 0,    ) {}}
export default rectangleArea;