// 第一题 var arr = [1, 2, 3, 4] function mess(index){ let res = arr.splice(index, 1)[0] arr.sort((a, b)=>Math.random()-0.5) arr.splice(index, 0, res) console.log(arr) } // 第二题 var str1 = '3.1.1'; var str2 = '3.1.1.1'; // 返回较大的数 function compare(v1, v2){ let res1 = v1.split('.') let res2 = v2.split('.') function giveZero(arr, start, end){ for(let i = start; i <= end; i++){ arr[i] = '0'; } } if(res1.length > res2.length){ giveZero(res2, res2.length, res1.length - 1) }else if(res1.length < res2.length){ giveZero(res1, res1.length, res2.length - 1) } return res1.join('') > res2.join('') ? v1 : v2 } let res = compare(str1, str2) console.log(res)