LeetCode -- Reverse Bits

题目描述


Reverse bits of a given 32 bits unsigned integer.


For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), return 964176192 (represented in binary as 00111001011110000010100101000000).


Follow up:
If this function is called many times, how would you optimize it?




反转一个无符号数字的二进制串。


思路：
将n转化字符串，反转字符串，将字符串转换为无符号数。


实现代码

public class Solution {    public uint reverseBits(uint n)     {    var s = ToBinaryStr(n);        var s1 = "";    for(var i = s.Length - 1; i >= 0; i--){    s1 += s[i];    }        var x = BinaryToN(s1);    return x;    }private string ToBinaryStr(uint n){var s = new uint[32];var counter = 0;while(n > 0){var l = n%2;s[31-counter] = l;n /= 2;counter ++;}return string.Join("",s);}private uint BinaryToN(string s){var n = 0;for(var i = s.Length - 1; i >= 0 ; i--){var x = s[i] == '0' ? 0 : 1;n += x * (int)Math.Pow(2, s.Length - i - 1);}return (uint)n;}}