Point

JS

/**
 * Point
 * -----
 * ```
 * new Point(x,y)
 * ```
 * ### methods
 * - p.turnRight()
 * - p.add(p2)
 * - p.isEqual(p2)
 * - p.copy()
 */
export class Point {
	
	// init
	constructor(x,y){
		this.x = x;
		this.y = y;
	}
	
	// point.turRight()
	turnRight(){
		const {x,y} = this; 
		this.x = y;
		this.y = -x;
        return this;
	}
	
	// p1.add(p2)
	add(point){
		const {x:x1, y:y1} = this;
		const {x:x2, y:y2} = point;
		return new Point(x1+x2, y1+y2);
	}
	
	// point.copy()
	copy(){
		return new Point(this.x, this.y);
	}

    // p1.isEqual(p2)
    isEqual(p2){
        return this.x === p2.x && this.y === p2.y;
    }
}

⬇️ 應用

• Spiral Matrix