const byteStrings = Array.from({ length: 256 }, (_, value) =>
    value.toString(16).padStart(2, "0")
);

class Test {
	offset = 0;
	array = [];
	
	constructor() {
		for (let i = 0; i <= (1000 * 16); i++)
		{
			this.array.push(Math.random() * 256 | 0);
		}
	}
	
	getGuid() {
		const guid = this.array[this.offset + 3].toString(16).padStart(2, '0') + this.array[this.offset + 2].toString(16).padStart(2, '0') + this.array[this.offset + 1].toString(16).padStart(2, '0') + this.array[this.offset + 0].toString(16).padStart(2, '0') + "-" +this.array[this.offset + 5].toString(16).padStart(2, '0') + this.array[this.offset + 4].toString(16).padStart(2, '0') + "-" +       this.array[this.offset + 7].toString(16).padStart(2, '0') + this.array[this.offset + 6].toString(16).padStart(2, '0') + "-" +this.array[this.offset + 8].toString(16).padStart(2, '0') + this.array[this.offset + 9].toString(16).padStart(2, '0') + "-" +this.array[this.offset + 10].toString(16).padStart(2, '0') + this.array[this.offset + 11].toString(16).padStart(2, '0') + this.array[this.offset + 12].toString(16).padStart(2, '0') + this.array[this.offset + 13].toString(16).padStart(2, '0') + this.array[this.offset + 14].toString(16).padStart(2, '0') + this.array[this.offset + 15].toString(16).padStart(2, '0');
    	this.offset += 16;
    	return guid;
	}
	
	getGuidV2() {
        const { array, offset } = this;
        const guid =byteStrings[array[offset + 3]]+byteStrings[array[offset + 2]]+byteStrings[array[offset + 1]]+byteStrings[array[offset + 0]]+"-"+byteStrings[array[offset + 5]]+byteStrings[array[offset + 4]]+"-" +byteStrings[array[offset + 7]]+byteStrings[array[offset + 6]]+"-"+byteStrings[array[offset + 8]]+byteStrings[array[offset + 9]]+"-"+byteStrings[array[offset + 10]]+byteStrings[array[offset + 11]]+byteStrings[array[offset + 12]]+byteStrings[array[offset + 13]]+byteStrings[array[offset + 14]]+byteStrings[array[offset + 15]];
        this.offset += 16;
        return guid;
    }
}

let test = new Test();