123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869
export default class TextEditor {    constructor() {}    #left = "";    #right = "";    #position = 0;
    get #length() {        return this.#left.length + this.#right.length;    }    #get(index: number) {        if (index < this.#left.length) {            return this.#left[index];        }        return this.#right[index - this.#left.length];    }    #slice(start = 0, end: number = this.#length): string {        start = Math.max(0, start);        end = Math.min(end, this.#length);        return Array(end - start)            .fill("")            .map((_, i) => this.#get(i + start))            .join("");    }    addText(text: string): void {        if (this.#position === this.#left.length) {            this.#left += text;            this.#position = this.#left.length;        } else {            const all_text = this.#left + this.#right;            this.#right = all_text.slice(this.#position, this.#length);            this.#left = all_text.slice(0, this.#position) + text;            this.#position = this.#left.length;        }    }
    deleteText(k: number): number {        if (this.#position === this.#left.length) {            const count = Math.min(k, this.#left.length);            const end = Math.max(0, this.#left.length - k);            this.#left = this.#left.slice(0, end);            this.#position = this.#left.length;            return count;        } else {            const all_text = this.#left + this.#right;            const count = Math.min(k, this.#position);            this.#right = all_text.slice(this.#position, this.#length);            const end = Math.max(0, this.#position - k);            this.#left = all_text.slice(0, end);            this.#position = this.#left.length;            return count;        }    }
    cursorLeft(k: number): string {        this.#position = Math.max(0, this.#position - k);
        return this.#read_left_ten();    }
    #read_left_ten(): string {        return this.#slice(Math.max(0, this.#position - 10), this.#position);    }
    cursorRight(k: number): string {        this.#position = Math.min(this.#length, this.#position + k);        return this.#read_left_ten();    }}