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function BrowserHistory(homepage: string) {    const array = [homepage];
    let index = 0;    return {        visit(url: string): void {            array.length = index + 1;            array.push(url);            index++;        },
        back(steps: number): string {            index = Math.max(index - steps, 0);            return array[index];        },
        forward(steps: number): string {            index = Math.min(index + steps, array.length - 1);            return array[index];        },    };}
type BrowserHistory = ReturnType<typeof BrowserHistory>;export default BrowserHistory;