1. 斐波那契 from itertools import islice def fib(): a, b = 0, 1 while True: yield a a, b = b, a+b print list(islice(fib(), 5)) # [0, 1, 1, 2, 3] 2. for……else……用法(以查找素数为例) 正常版本: def print_prime(n): for i in xrange(2, n): found = True for j in xrange(2, i)
137. Single Number II Given an array of integers, every element appears three times except for one. Find that single one. Note:Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 记录32个bit每个bit出现的
group by 最后一个时间是多少按多少分组 select count(1), trunc(a.refund_insert_time, 'hh24') + case when to_char(refund_insert_time,'mi') >= '30' then numtodsinterval(30,'minute') else numtodsinterval(0,'minute') end from refund_record a where a.refund_complete_time
昨天看了编程珠玑第一章的内容, 发现bitmap对于统计某一个范围内的整数个数效率很高, 就自己实现了一下: 这是原始的bitmap, 用于统计0~maxSize是否出现, 也可以用于排序 public class BitMap { private int[] arr ; private final int mask = 0X1F ; //用于表示偏移量 private final int shift = 5 ; //用于表示index处于arr的第几个 public BitMap(int ma
package main import "fmt" //通过键盘输入20个小写字母,统计个数 func main(){ //通过键盘器获取字符 var arr [20]byte for i :=0;i< len(arr); i++{ fmt.Scanf("%c",&arr[i]) } //用来统计字符个数 下标0位啊,25为z var ch[26] int //记录字母出现的次数 for i:=0; i< len(arr) ;i++ { ch[a
