diff --git a/problems/0027.移除元素.md b/problems/0027.移除元素.md index 693684f3..99990302 100644 --- a/problems/0027.移除元素.md +++ b/problems/0027.移除元素.md @@ -197,7 +197,23 @@ var removeElement = (nums, val) => { }; ``` +TypeScript: + +```typescript +function removeElement(nums: number[], val: number): number { + let slowIndex: number = 0, fastIndex: number = 0; + while (fastIndex < nums.length) { + if (nums[fastIndex] !== val) { + nums[slowIndex++] = nums[fastIndex]; + } + fastIndex++; + } + return slowIndex; +}; +``` + Ruby: + ```ruby def remove_element(nums, val) i = 0 diff --git a/problems/0028.实现strStr.md b/problems/0028.实现strStr.md index ef7008bc..f0b56719 100644 --- a/problems/0028.实现strStr.md +++ b/problems/0028.实现strStr.md @@ -649,6 +649,41 @@ class Solution { } ``` +```Java +class Solution { + //前缀表(不减一)Java实现 + public int strStr(String haystack, String needle) { + if (needle.length() == 0) return 0; + int[] next = new int[needle.length()]; + getNext(next, needle); + + int j = 0; + for (int i = 0; i < haystack.length(); i++) { + while (j > 0 && needle.charAt(j) != haystack.charAt(i)) + j = next[j - 1]; + if (needle.charAt(j) == haystack.charAt(i)) + j++; + if (j == needle.length()) + return i - needle.length() + 1; + } + return -1; + + } + + private void getNext(int[] next, String s) { + int j = 0; + next[0] = 0; + for (int i = 1; i < s.length(); i++) { + while (j > 0 && s.charAt(j) != s.charAt(i)) + j = next[j - 1]; + if (s.charAt(j) == s.charAt(i)) + j++; + next[i] = j; + } + } +} +``` + Python3: ```python diff --git a/problems/0077.组合.md b/problems/0077.组合.md index 8e944eb3..2bd7a287 100644 --- a/problems/0077.组合.md +++ b/problems/0077.组合.md @@ -422,13 +422,13 @@ class Solution: def backtrack(n,k,startIndex): if len(path) == k: res.append(path[:]) - return + return for i in range(startIndex,n - (k - len(path)) + 2): #优化的地方 path.append(i) #处理节点 backtrack(n,k,i+1) #递归 path.pop() #回溯,撤销处理的节点 - backtrack(n,k,1) - return res + backtrack(n,k,1) + return res ``` diff --git a/problems/0077.组合优化.md b/problems/0077.组合优化.md index bd941e03..e995fd18 100644 --- a/problems/0077.组合优化.md +++ b/problems/0077.组合优化.md @@ -182,13 +182,13 @@ class Solution: def backtrack(n,k,startIndex): if len(path) == k: res.append(path[:]) - return + return for i in range(startIndex,n-(k-len(path))+2): #优化的地方 path.append(i) #处理节点 backtrack(n,k,i+1) #递归 path.pop() #回溯,撤销处理的节点 - backtrack(n,k,1) - return res + backtrack(n,k,1) + return res ``` Go: ```Go diff --git a/problems/0209.长度最小的子数组.md b/problems/0209.长度最小的子数组.md index 80822436..17422ca0 100644 --- a/problems/0209.长度最小的子数组.md +++ b/problems/0209.长度最小的子数组.md @@ -107,7 +107,7 @@ public: }; ``` -时间复杂度:$O(n)$ +时间复杂度:$O(n)$ 空间复杂度:$O(1)$ **一些录友会疑惑为什么时间复杂度是$O(n)$**。 @@ -121,7 +121,6 @@ public: - ## 其他语言版本 @@ -214,6 +213,28 @@ var minSubArrayLen = function(target, nums) { }; ``` +Typescript: + +```typescript +function minSubArrayLen(target: number, nums: number[]): number { + let left: number = 0, right: number = 0; + let res: number = nums.length + 1; + let sum: number = 0; + while (right < nums.length) { + sum += nums[right]; + if (sum >= target) { + // 不断移动左指针,直到不能再缩小为止 + while (sum - nums[left] >= target) { + sum -= nums[left++]; + } + res = Math.min(res, right - left + 1); + } + right++; + } + return res === nums.length + 1 ? 0 : res; +}; +``` + Swift: ```swift @@ -291,5 +312,23 @@ class Solution { } ``` +Ruby: + +```ruby +def min_sub_array_len(target, nums) + res = Float::INFINITY # 无穷大 + i, sum = 0, 0 + nums.length.times do |j| + sum += nums[j] + while sum >= target + res = [res, j - i + 1].min + sum -= nums[i] + i += 1 + end + end + res == Float::INFINITY ? 0 : res +end +``` + -----------------------
* 入站元素要和当前栈内栈首元素进行比较 * 若大于栈首则 则与元素下标做差 diff --git a/problems/0977.有序数组的平方.md b/problems/0977.有序数组的平方.md index 0085de0b..b11fa7ef 100644 --- a/problems/0977.有序数组的平方.md +++ b/problems/0977.有序数组的平方.md @@ -221,6 +221,35 @@ var sortedSquares = function(nums) { }; ``` +Typescript: + +双指针法: + +```typescript +function sortedSquares(nums: number[]): number[] { + let left: number = 0, right: number = nums.length - 1; + let resArr: number[] = new Array(nums.length); + let resArrIndex: number = resArr.length - 1; + while (left <= right) { + if (Math.abs(nums[left]) < Math.abs(nums[right])) { + resArr[resArrIndex] = nums[right--] ** 2; + } else { + resArr[resArrIndex] = nums[left++] ** 2; + } + resArrIndex--; + } + return resArr; +}; +``` + +骚操作法(暴力思路): + +```typescript +function sortedSquares(nums: number[]): number[] { + return nums.map(i => i * i).sort((a, b) => a - b); +}; +``` + Swift: ```swift