LeetCode Reverse Bits

Description

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).

The original problem is here:

My Solution

I solve this problem in Python, as below:

class Solution:
    # @param n, an integer
    # @return an integer
    def reverseBits(self, n):
        bits = [0] * 32;
        rev_bits = [0] * 32;
        bits = self.integer2binary(n)
        for i in range(len(bits)):
            rev_bits[i] = bits[31-i]
        rev_n = self.binary2integer(rev_bits)
        return rev_n
    def integer2binary(self,n):
        bits = [0]*32
        i = 31
        while(n>0):
            bits[i] = n % 2
            n = n/2
            i -=1
        return bits
    def binary2integer(self,bits):
        n = 0
        bits_len = len(bits)
        for i in range(len(bits)):
            n += bits[i]*pow(2,bits_len-i-1)
        return n


#The code under below is used for test
#n=43261596
#S = Solution()
#print S.reverseBits(n)

Note

This problem can be parted as two parts: one is integer2binary and the other is binary2integer. Then it is easy to solve this problem.