/**
 * 验证IP地址
 * @param IP string字符串 一个IP地址字符串
 * @return string字符串
 */
function solve( IP ) {
    // write code here
    const arr4 = IP.split(".")
    const arr6 = IP.split(":")
    const ex4 = /^0$|^[1-9]\d{0,2}$/
    const ex6 = /^[0-9a-fA-F]{1,4}$/
    if(arr4.length==4 && arr4.every(item => item.match(ex4) && item < 256)){
            return "IPv4"
    }else if(arr6.length==8 && arr6.every(item => item.match(ex6)) ){
            return "IPv6"
    }
    return "Neither"
}
module.exports = {
    solve : solve
};