10進数から2進数 2進数から10進数への変換 JavaScript

function intToBin(num) {
    let ans = []
    if (num === 0) {
        return '0'
    }
    while (num > 0) {
        ans.push(num%2)
        num = Math.floor(num / 2)
    }
    return ans.reverse().join('')
}

function binToInt(str) {
    let nums = str.split("").map(Number).reverse()
    let ans = 0
    for (let i = 0; i < nums.length; i++) {
        ans += (2 ** i) * nums[i]
    }
    return ans
}

const max = 10e5
for (let i = 0; i < max; i++) {
    console.log(i)
    if (intToBin(i) !== i.toString(2)) {
        console.log("error:1")
        break
    }
    let bin = i.toString(2)
    if (binToInt(bin) !== parseInt(bin, 2)) {
        console.log("error:2")
        break
    }
}