exercism-ts/difference-of-squares/difference-of-squares.ts

export class Squares {
    constructor(private count: number) {
    }

    get sumOfSquares(): number {
        let sum = 0;
        for (let i = 0; i <= this.count; i++) {
            sum += i * i;
        }
        return sum;
    }

    get squareOfSum(): number {
        let sum = this.count * (this.count + 1) / 2;
        return sum * sum;
    }

    get difference(): number {
        return this.squareOfSum-this.sumOfSquares;
    }
}