<pre><code class="language-javascript">
/**
 * @param {string} str
 * @return {boolean}
 */
function isValidIP(str){
    const ipv4Reg = /\d+(?=\.)/g;
    const ipv6Reg = /[0-9a-zA-Z]+(?=\:)/g
    if(ipv4Reg.test(str)){
        const matchNum = str.split('.');
        if(matchNum.length !== 4){
            return false;
        } else {
            for(let num of matchNum){
                if(num === '00' || isNaN(parseInt(num)) || Number(num) !==0 &amp;&amp; (num.startsWith('0')) || Number(num)&gt;255){
                    return false;
                }
            }
            return true;
        }
    } else if (ipv6Reg.test(str)){
        const matchNum = str.split(':');
        if(matchNum.length!==8){
            return false;
        } else {
            for (let _item of matchNum) {
              const item = _item.toLowerCase();
              const num = parseInt(item, 16);
              if (isNaN(num)) return false;
              if (num &lt; 0 || num &gt; 0xffff) return false;
              if (num.toString(16).padStart(item.length, '0') !== item) return false;
            }
            return true;
        }
    }
    return false;
}
</code></pre>


This is my accepted solution

IPV4 An IPv4 Address is represented in dot-decimal notation, consisting of 4 numbers( called 'octet'), each ranging from 0 to 255, like 1.22.33.255. I…

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