question3.js

let hex = "F2AB7D"; // Equivalent to rgb(242,171,125)
let rgb = [242, 171, 125]; // Equivalente to the upper hex value


const hexTable = number => {

	if (parseInt(number) < 10) return parseInt(number);
	
	else {
		switch(number) {
			case 10: return "A";
				break;
			case 11: return "B";
				break;
			case 12: return "C";
				break;
			case 13: return "D";
				break;
			case 14: return "E";
				break;
			case 15: return "F";
				break;

			case "A": return 10;
				break;
			case "B": return 11;
				break;
			case "C": return 12;
				break;
			case "D": return 13;
				break;
			case "E": return 14;
				break;
			case "F": return 15;
				break;
		}
	}
}

const HEXandRGB = value => {
	//if is hex / TO RGB
	if (value.length === 6) {
		let rgb = new Array(3);

		rgb[0] = (hexTable(value[0])*16) + hexTable(value[1]);
		rgb[1] = (hexTable(value[2])*16) + hexTable(value[3]);
		rgb[2] = (hexTable(value[4])*16) + hexTable(value[5]);
		return rgb;

	} 
	// if is rgb / TO HEX
	else if (value.length === 3) {
		
		let hex = "";
		for (let i=0; i<3; i++) hex += hexTable(Math.floor(value[i]/16)) + hexTable(value[i]%16);

		return hex;
	} 
	else return undefined;
}

// Testing HEXandRGB function
console.log(HEXandRGB(hex));
console.log(HEXandRGB(rgb));