标签：
Reverse bits of a given 32 bits unsigned integer.
For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), return 964176192 (represented in binary as00111001011110000010100101000000).
Follow up:
If this function is called many times, how would you optimize it?
Related problem: Reverse Integer
Credits:
Special thanks to @ts for adding this problem and creating all test cases.
Bit Manipulation
这道题目的意思是将一个32位字节存储的一个数，在二进制上前后旋转，然后得到一个新的二进制数，再将二进制数转换成unsigned long型的数输出
所以这道题用C++做的话很简单，主要是考虑bitset的使用（初始化和使用函数to_ulong）
#include<iostream>
#include <bitset>
using namespace std;
typedef unsigned long uint32_t;
uint32_t reverseBits(uint32_t n) {
uint32_t result;
//unsigned long val=n;
int val=n;
bitset<32>bit_temp(val);
for(int i=0;i<16;i++)
{
bool temp;
temp=bit_temp[i];
bit_temp[i]=bit_temp[31-i];
bit_temp[31-i]=temp;
}
result=bit_temp.to_ulong();
return result;
}
int main()
{
//cout<<reverseBits(1)<<endl;
unsigned long a=12;
cout<<sizeof(unsigned long)<<endl;
cout<<sizeof(int)<<endl;
cout<<sizeof(long)<<endl;
bitset<32> temp(a);
}
leetcode_190题——Reverse Bits（bitset的使用）
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原文地址：http://www.cnblogs.com/yanliang12138/p/4470739.html
