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;
}
}