convert decimal to binary javascript

function dec2bin(dec){
    return (dec >>> 0).toString(2);
}

dec2bin(1);    // 1
dec2bin(-1);   // 11111111111111111111111111111111
dec2bin(256);  // 100000000
dec2bin(-256); // 11111111111111111111111100000000

var n = 5;
n.toString(2); // "101"

var digit = parseInt(binary, 2);

// program to convert decimal to binary
function convertToBinary(x) {
    let bin = 0;
    let rem, i = 1, step = 1;
    while (x != 0) {
        rem = x % 2;
        console.log(
            `Step ${step++}: ${x}/2, Remainder = ${rem}, Quotient = ${parseInt(x/2)}`
        );
        x = parseInt(x / 2);
        bin = bin + rem * i;
        i = i * 10;
    }
    console.log(`Binary: ${bin}`);
}

// take input
let number = prompt('Enter a decimal number: ');

convertToBinary(number);

const binaryArrayToNumber = arr => {
    let len = arr.length
    let pow = []
    let decimal = []
    for(let i = 0; i <= len - 1; i++){
        pow.unshift(i)
    }
    arr.forEach((x,index) => {
        decimal.push(x*2**pow[index])
    })
    let toDecimal = decimal.reduce((acc, curr) => acc + curr, 0)
    return toDecimal
};
console.log(binaryArrayToNumber([1, 0, 1, 1]))