You are given an arraynumsthat consists of non-negative integers. Let us definerev(x)as the reverse of the non-negative integerx. For example,rev(123) = 321, andrev(120) = 21. A pair of indices(i, j)isniceif it satisfies all of the following conditions: 0 <= i < j < nums.l...
Leetcode 1814. Count Nice Pairs in an Array 2. Solution **解析:**Version 1,由题目可知nums[i] - rev(nums[i])相等的两个数即可构成一个合适的对,因此统计nums[i] - rev(nums[i])相等的数值即可。 Version 1 代码语言:javascript 代码运行次数:0 classSolution:defcountNicePairs(self,nums:List[in...
Given an array of integersnumsand an integerk. A continuous subarray is called nice if there arekodd numbers on it. Returnthe number of nice sub-arrays. Example 1: Input:nums = [1,1,2,1,1], k =3Output:2Explanation:The onlysub-arrayswith3odd numbers are [1,1,2,1]and[1,2,1,...
Given an integer array nums, return the number of range sums that lie in [lower, upper] inclusive. Range sum S(i, j) is defined as the sum of the elements in nums between indices i and j (i ≤ j), inclusive. Note: A naive algorithm of O(n2) is trivial. You MUST do better t...
Give a strings, count the number of non-empty (contiguous) substrings that have the same number of 0's and 1's, and all the 0's and all the 1's in these substrings are grouped consecutively. Substrings that occur multiple times are counted the number of times they occur. ...
Given a 2D integer array circles where circles[i] = [xi, yi, ri] represents the center (xi, yi) and radius ri of the ith circle drawn on a grid, return the number of lattice points that are present inside at least one circle. Note: A lattice point is a point with integer coordina...
LeetCode-Count Bits Given a non negative integer numbernum. For every numbersiin the range0 ≤ i ≤ numcalculate the number of 1's in their binary representation and return them as an array. Example: Fornum = 5you should return[0,1,1,2,1,2]....
count(\*) 其实等于 count(0),也就是说,当你使用 count(*)时,MySQL 会将 * 参数转化为参数 0 来处理。 所以,count(*) 执行过程跟 count(1) 执行过程基本一样的,性能没有什么差异。 在MySQL 5.7 的官方手册中有这么一句话: InnoDB handles SELECT COUNT(\*) and SELECT COUNT(1) operations in the ...
例题1 - LeetCode剑指 Offer 51. 数组中的逆序对 题目 在数组中的两个数字,如果前面一个数字大于后面的数字,则这两个数字组成一个逆序对。输入一个数组,求出这个数组中的逆序对的总数。 输入: [7,5,6,4] 输出: 5 限制:0 <= 数组长度 <= 50000 ...
count(1)：这个查询与count(*)类似，统计表中的总行数。在某些情况下，count(1)可能稍微慢于count(*...