LeetCode1—10 JavaScript解法

1.TwoSum

var twoSum =function(nums, target) {       for(var i=0; i<nums.length-1; i++){        for(var j=i+1; j<nums.length; j++){            if(target == nums[i]+nums[j]){                               return [i,j];            }        }    }};

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2.AddTwo Numbers

我没搞懂！！

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3.Longest Substring Without Repeating Characters

varlengthOfLongestSubstring = function(s) {    let result = 0    let res = []    for (var i = 0; i < s.length; i++) {        if (res.includes(s[i])) {            res = res.slice(res.indexOf(s[i]) +1)        }        res.push(s[i])        if (res.length > result) {            result =res.length;        }    }    return result};

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4.Median of Two Sorted Arrays

varfindMedianSortedArrays = function(nums1, nums2) {    var arr = nums1.concat(nums2);    arr = arr.sort(function(a,b){return a-b});    //return arr;    var len = arr.length;    if(len%2 === 0){        return (arr[len/2-1]+arr[len/2])/2;    }else{        return (arr[(len+1)/2-1]);    }};

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5.Longest Palindromic Substring

varlongestPalindrome = function(s) {    var res = '';    var len = 0;    for(var i=0; i<s.length;i++){        for(var j=i; j<s.length; j++){            var tem = s.slice(i,j+1);            if( tem ===tem.split('').reverse().join('')){                                  if(tem.length >res.length) res = tem;            }                   }     }    return res;};

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6.ZigZagConversion
没做出来

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7.Reverse Integer

var reverse =function(x) {   if(x<10 && x>-10) return x;   var tem = x > 0 ? x :-x;   var y = 0;   while(tem > 0){       y = y * 10 + tem % 10;       tem = Math.floor(tem/10);   }   if(y > Math.pow(2,31)-1) return 0;   return x > 0 ? y : -y;    };

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8.Stringto Integer (atoi)

 var myAtoi = function(str) {   var str = str.trim();   var index = str.search(/[^+-\d]/);   var sub;   if (index < 0) sub = str;    else sub = str.substr(0, index);   var num = Number(sub);   if (isNaN(num)) num = 0;   if(num >= 2147483647) num = 2147483647;   else if(num <= -2147483648) num = -2147483648;   return num;};

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9.Palindrome Number

var isPalindrome = function(x) {   if(x<0) return false;   if(x<10){       return true;   }else{       var y = x.toString().split('');       y = y.reverse().join('');       return x === parseInt(y);   }    };

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10.Regular Expression Matching

varisMatch = function(s, p) {   var reg = new RegExp(p)   var res = s.match(reg);   if(res === null) return false;   return res == s;};