匹配IP地址

function judge(str) {
    if(str.length < 7 || str.length > 15) {
        return false
    }
    var arr = str.split('.')
    len = arr.length
    for (var i=0; i<len; i++) {
        if(isNaN(arr[i])) {
            return false
        }
        if (arr[i] <0 ||arr[i] >255) {
            return false
        }
    }
    return true

}

console.log(judge('1.2.3.5'))