原题 水题 唯一注意的点就是数字溢出 class Solution { public: int reverse(int x) { long long MAX = ((long long)1 << 31) - 1; long long MIN = 0 - (1 << 31); long long a = 0; while (x) { a = a * 10 + x % 10; x /= 10; } return a > MAX || a < MIN ? 0 : a; } }…

7. Reverse Integer Easy Given a 32-bit signed integer, reverse digits of an integer. Example 1: Input: 123 Output: 321 Example 2: Input: -123 Output: -321 Example 3: Input: 120 Output: 21 Note: Assume we are dealing with an environment which could on…

题目来源:https://leetcode.com/problems/reverse-integer/ Reverse digits of an integer. Example1: x = 123, return 321Example2: x = -123, return -321 解题思路: 其实这道题看起来非常简单,要实现也是几行代码的事.但是有个小问题容易被忽略,就是边界问题.什么意思呢?如果我们输入的整数超出了int的表达范围,这个问题要怎么解决呢? 用比int更大的数据类型存储我们转…

Reverse Integer Reverse digits of an integer. Example1: x = 123, return 321Example2: x = -123, return -321 click to show spoilers. Have you thought about this? Here are some good questions to ask before coding. Bonus points for you if you have alread…

Reverse Integer 想用余10直接算,没想到 -123%10 是 7, 原因 -123-(-123//10*10) r=a-n*[a/n] 以上,r是余数,a是被除数,n是除数. 唯一不同点,就是商向0或负无穷方向取整的选择,c从c99开始规定向0取整,python则规定向负无穷取整,选择而已. 所以套用上述公式为: C 语言:(a%n的符号与a相同) -9%7=-9 - 7*[-1]=-2: 9%-7=9 - -7*[-1]=2; Python语言::(a%n的符号与n相同) -9…

题目 Reverse digits of an integer. Example1: x = 123, return 321 Example2: x = -123, return -321 Have you thought about this? Here are some good questions to ask before coding. Bonus points for you if you have already thought through this! If the integ…

Question:Reverse digits of an integer. Example1: x = 123, return 321Example2: x = -123, return -321 Have you thought about this? Here are some good questions to ask before coding. Bonus points for you if you have already thought through this! If the…

problem: Reverse digits of an integer. Example1: x = 123, return 321 Example2: x = -123, return -321 thinking: (1)整型反转直观非常easy理解. 如正负,尾数为0等问题还优点理. (2)反转溢出问题要细致处理. code: class Solution { public: int reverse(int x) { long long int y=x; bool flag=true;…

# -*- coding: utf8 -*-'''__author__ = 'dabay.wang@gmail.com'https://oj.leetcode.com/problems/reverse-integer/ Reverse digits of an integer. Example1: x = 123, return 321Example2: x = -123, return -321 Have you thought about this?Here are some good qu…

这道题是LeetCode里的第7道题. 题目描述: 给出一个 32 位的有符号整数,你需要将这个整数中每位上的数字进行反转. 示例 1: 输入: 123 输出: 321  示例 2: 输入: -123 输出: -321 示例 3: 输入: 120 输出: 21 注意: 假设我们的环境只能存储得下 32 位的有符号整数,则其数值范围为 [−231,  231 − 1].请根据这个假设,如果反转后整数溢出那么就返回 0. 首先,这是一道简单题,根据我多年的做题经验来看,这道题肯定有坑,绝对会有 IN…