diff --git a/README.md b/README.md index 1d7f219d..38418322 100644 --- a/README.md +++ b/README.md @@ -531,7 +531,8 @@ 如果是已工作，备注：姓名-城市-岗位-组队刷题。如果学生，备注：姓名-学校-年级-组队刷题。**备注没有自我介绍不通过哦** -
+ +
@@ -543,6 +544,7 @@ **来看看就知道了，你会发现相见恨晚！** +
diff --git a/problems/0027.移除元素.md b/problems/0027.移除元素.md index 8d6ca502..590cf0b9 100644 --- a/problems/0027.移除元素.md +++ b/problems/0027.移除元素.md @@ -281,10 +281,8 @@ func removeElement(_ nums: inout [Int], _ val: Int) -> Int { for fastIndex in 0.. 贪心法： +```Go +func maxProfit(prices []int) int { + low := math.MaxInt32 + rlt := 0 + for i := range prices{ + low = min(low, prices[i]) + rlt = max(rlt, prices[i]-low) + } + return rlt +} +func min(a, b int) int { + if a < b{ + return a + } + + return b +} + +func max(a, b int) int { + if a > b{ + return a + } + + return b +} +``` + +> 动态规划：版本一 ```Go func maxProfit(prices []int) int { length:=len(prices) @@ -338,6 +367,29 @@ func max(a,b int)int { } ``` +> 动态规划：版本二 +```Go +func maxProfit(prices []int) int { + dp := [2][2]int{} + dp[0][0] = -prices[0] + dp[0][1] = 0 + for i := 1; i < len(prices); i++{ + dp[i%2][0] = max(dp[(i-1)%2][0], -prices[i]) + dp[i%2][1] = max(dp[(i-1)%2][1], dp[(i-1)%2][0]+prices[i]) + } + + return dp[(len(prices)-1)%2][1] +} + +func max(a, b int) int { + if a > b{ + return a + } + + return b +} +``` + JavaScript: > 动态规划 diff --git a/problems/0122.买卖股票的最佳时机II.md b/problems/0122.买卖股票的最佳时机II.md index 4f585a3c..78aa5952 100644 --- a/problems/0122.买卖股票的最佳时机II.md +++ b/problems/0122.买卖股票的最佳时机II.md @@ -264,7 +264,7 @@ const maxProfit = (prices) => { dp[i][1] = Math.max(dp[i-1][1], dp[i-1][0] + prices[i]); } - return dp[prices.length -1][0]; + return dp[prices.length -1][1]; }; ``` diff --git a/problems/0122.买卖股票的最佳时机II（动态规划）.md b/problems/0122.买卖股票的最佳时机II（动态规划）.md index 615d79bb..5a165a14 100644 --- a/problems/0122.买卖股票的最佳时机II（动态规划）.md +++ b/problems/0122.买卖股票的最佳时机II（动态规划）.md @@ -276,7 +276,7 @@ const maxProfit = (prices) => { dp[i][1] = Math.max(dp[i-1][1], dp[i-1][0] + prices[i]); } - return dp[prices.length -1][0]; + return dp[prices.length -1][1]; }; // 方法二：动态规划（滚动数组） diff --git a/problems/0135.分发糖果.md b/problems/0135.分发糖果.md index ccdabc16..b8bdae0e 100644 --- a/problems/0135.分发糖果.md +++ b/problems/0135.分发糖果.md @@ -238,6 +238,32 @@ var candy = function(ratings) { }; ``` +### TypeScript + +```typescript +function candy(ratings: number[]): number { + const candies: number[] = []; + candies[0] = 1; + // 保证右边高分孩子一定比左边低分孩子发更多的糖果 + for (let i = 1, length = ratings.length; i < length; i++) { + if (ratings[i] > ratings[i - 1]) { + candies[i] = candies[i - 1] + 1; + } else { + candies[i] = 1; + } + } + // 保证左边高分孩子一定比右边低分孩子发更多的糖果 + for (let i = ratings.length - 2; i >= 0; i--) { + if (ratings[i] > ratings[i + 1]) { + candies[i] = Math.max(candies[i], candies[i + 1] + 1); + } + } + return candies.reduce((pre, cur) => pre + cur); +}; +``` + + + -----------------------
diff --git a/problems/0406.根据身高重建队列.md b/problems/0406.根据身高重建队列.md index b2354d09..ecb05301 100644 --- a/problems/0406.根据身高重建队列.md +++ b/problems/0406.根据身高重建队列.md @@ -290,6 +290,24 @@ var reconstructQueue = function(people) { }; ``` +### TypeScript + +```typescript +function reconstructQueue(people: number[][]): number[][] { + people.sort((a, b) => { + if (a[0] === b[0]) return a[1] - b[1]; + return b[0] - a[0]; + }); + const resArr: number[][] = []; + for (let i = 0, length = people.length; i < length; i++) { + resArr.splice(people[i][1], 0, people[i]); + } + return resArr; +}; +``` + + + -----------------------
diff --git a/problems/0416.分割等和子集.md b/problems/0416.分割等和子集.md index b24fb365..6e93ae8e 100644 --- a/problems/0416.分割等和子集.md +++ b/problems/0416.分割等和子集.md @@ -50,7 +50,7 @@ ## 01背包问题 -背包问题，大家都知道，有N件物品和一个最多能被重量为W 的背包。第i件物品的重量是weight[i]，得到的价值是value[i] 。每件物品只能用一次，求解将哪些物品装入背包里物品价值总和最大。 +背包问题，大家都知道，有N件物品和一个最多能背重量为W 的背包。第i件物品的重量是weight[i]，得到的价值是value[i] 。每件物品只能用一次，求解将哪些物品装入背包里物品价值总和最大。 **背包问题有多种背包方式，常见的有：01背包、完全背包、多重背包、分组背包和混合背包等等。** diff --git a/problems/0503.下一个更大元素II.md b/problems/0503.下一个更大元素II.md index ead31c8b..ace4d40b 100644 --- a/problems/0503.下一个更大元素II.md +++ b/problems/0503.下一个更大元素II.md @@ -166,20 +166,19 @@ JavaScript: * @return {number[]} */ var nextGreaterElements = function (nums) { - // let map = new Map(); + const len = nums.length; let stack = []; - let res = new Array(nums.length).fill(-1); - for (let i = 0; i < nums.length * 2; i++) { + let res = Array(len).fill(-1); + for (let i = 0; i < len * 2; i++) { while ( stack.length && - nums[i % nums.length] > nums[stack[stack.length - 1]] + nums[i % len] > nums[stack[stack.length - 1]] ) { - let index = stack.pop(); - res[index] = nums[i % nums.length]; + const index = stack.pop(); + res[index] = nums[i % len]; } - stack.push(i % nums.length); + stack.push(i % len); } - return res; }; ``` diff --git a/problems/0739.每日温度.md b/problems/0739.每日温度.md index 710f5eb6..5f53e412 100644 --- a/problems/0739.每日温度.md +++ b/problems/0739.每日温度.md @@ -301,25 +301,22 @@ func dailyTemperatures(num []int) []int { JavaScript： ```javascript -/** - * @param {number[]} temperatures - * @return {number[]} - */ +// 版本一 var dailyTemperatures = function(temperatures) { - let n = temperatures.length; - let res = new Array(n).fill(0); - let stack = []; // 递减栈：用于存储元素右面第一个比他大的元素下标 + const n = temperatures.length; + const res = Array(n).fill(0); + const stack = []; // 递增栈：用于存储元素右面第一个比他大的元素下标 stack.push(0); for (let i = 1; i < n; i++) { // 栈顶元素 - let top = stack[stack.length - 1]; + const top = stack[stack.length - 1]; if (temperatures[i] < temperatures[top]) { stack.push(i); } else if (temperatures[i] === temperatures[top]) { stack.push(i); } else { while (stack.length && temperatures[i] > temperatures[stack[stack.length - 1]]) { - let top = stack.pop(); + const top = stack.pop(); res[top] = i - top; } stack.push(i); @@ -327,6 +324,23 @@ var dailyTemperatures = function(temperatures) { } return res; }; + + +// 版本二 +var dailyTemperatures = function(temperatures) { + const n = temperatures.length; + const res = Array(n).fill(0); + const stack = []; // 递增栈：用于存储元素右面第一个比他大的元素下标 + stack.push(0); + for (let i = 1; i < n; i++) { + while (stack.length && temperatures[i] > temperatures[stack[stack.length - 1]]) { + const top = stack.pop(); + res[top] = i - top; + } + stack.push(i); + } + return res; +}; ``` diff --git a/problems/0860.柠檬水找零.md b/problems/0860.柠檬水找零.md index ffd5490d..5d5d6ad2 100644 --- a/problems/0860.柠檬水找零.md +++ b/problems/0860.柠檬水找零.md @@ -252,5 +252,39 @@ var lemonadeChange = function(bills) { ``` +### TypeScript + +```typescript +function lemonadeChange(bills: number[]): boolean { + let five: number = 0, + ten: number = 0; + for (let bill of bills) { + switch (bill) { + case 5: + five++; + break; + case 10: + if (five < 1) return false; + five--; + ten++ + break; + case 20: + if (ten > 0 && five > 0) { + five--; + ten--; + } else if (five > 2) { + five -= 3; + } else { + return false; + } + break; + } + } + return true; +}; +``` + + + -----------------------
diff --git a/problems/1047.删除字符串中的所有相邻重复项.md b/problems/1047.删除字符串中的所有相邻重复项.md index 54455f62..638c8f4e 100644 --- a/problems/1047.删除字符串中的所有相邻重复项.md +++ b/problems/1047.删除字符串中的所有相邻重复项.md @@ -250,11 +250,9 @@ func removeDuplicates(s string) string { javaScript: +法一：使用栈 + ```js -/** - * @param {string} s - * @return {string} - */ var removeDuplicates = function(s) { const stack = []; for(const x of s) { @@ -267,6 +265,25 @@ var removeDuplicates = function(s) { }; ``` +法二：双指针（模拟栈） + +```js +// 原地解法（双指针模拟栈） +var removeDuplicates = function(s) { + s = [...s]; + let top = -1; // 指向栈顶元素的下标 + for(let i = 0; i < s.length; i++) { + if(top === -1 || s[top] !== s[i]) { // top === -1 即空栈 + s[++top] = s[i]; // 入栈 + } else { + top--; // 推出栈 + } + } + s.length = top + 1; // 栈顶元素下标 + 1 为栈的长度 + return s.join(''); +}; +``` + TypeScript： ```typescript