Write a function that reverses a string. The input string is given as an array of characterschar[]. Do not allocate extra space for another array, you must do this by modifying the input arrayin-placewith O(1) extra memory. You may assume all the characters consist ofprintable ascii char...
所以,为了提高大家的算法能力,这个公众号后续每天带大家做一道算法题,题目就从LeetCode上面选 ! 今天和大家聊的问题叫做翻转对,我们先来看题面: leetcode-cn.com/problem Givenanintegerarraynums,returnthenumberofreversepairsinthearray. Areversepairisapair(i,j)where0<=i<j<nums.lengthandnums[i]>2*nums...
具体实现代码如下：//字符串intpublicstaticintReverseIntString(intx){//把值转为字符串，并去掉负号'...
Try to come up as many solutions as you can, there are at least 3 different ways to solve this problem. [show hint] Hint: Could you do it in-place with O(1) extra space? Related problem: Reverse Words in a String II 题目标签:Array 题目给了我们一个数组 和 k。 让我们 旋转数组 k...
publicvoidrotate(int[]nums,int k){if(nums==null||nums.length<2){return;}k=k%nums.length;reverse(nums,0,nums.length-k-1);reverse(nums,nums.length-k,nums.length-1);reverse(nums,0,nums.length-1);}privatevoidreverse(int[]nums,int i,int j){int tmp=0;while(i<j){tmp=nums[i];num...
给定一个整数数组nums,将数组中的元素向右轮转k个位置,其中k是非负数。 示例1: 输入:nums = [1,2,3,4,5,6,7], k = 3输出:[5,6,7,1,2,3,4]解释:向右轮转 1 步:[7,1,2,3,4,5,6]向右轮转 2 步:[6,7,1,2,3,4,5]向右轮转 3 步:[5,6,7,1,2,3,4] ...
You are given a binary tree in which each node contains an integer value.Find the number of paths that sum to a given value.The path does not need to start or end at the root or a leaf, but it must go downwards (traveling only from parent nodes to child nodes). The tree has no...
Search in Rotated Sorted Array II 30.9% Medium Multiply Strings 【题目】Given two numbers represented as strings, return multiplication of the numbers as a string. Note: The numbers can be arbitrarily large and are non-negative. 【解答】按照自己在草稿上计算多位数乘以多位数的的方法那样计算,这种...
You are given an array of stringstokensthat represents an arithmetic expression in aReverse Polish Notation. Evaluate the expression. Returnan integer that represents the value of the expression. Notethat: The valid operators are'+','-','*', and'/'. ...
int N; long[] tr; public int reversePairs(int[] nums) { List<Long> ys = new ArrayList(); for(int i: nums) {//离散化 ys.add((long)i); ys.add((long)i * 2); } Collections.sort(ys);//排序 ys = unique(ys);//去重 N = ys.size(); tr = new long[N + 1];//树状数组...