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reverse bits (best solution) | leetcode solution| leetcode 190

 Reverse bits of a given 32 bits unsigned integer.



Note:

  • Note that in some languages, such as Java, there is no unsigned integer type. In this case, both input and output will be given as a signed integer type. They should not affect your implementation, as the integer's internal binary representation is the same, whether it is signed or unsigned.
  • In Java, the compiler represents the signed integers using 2's complement notation. Therefore, in Example 2 above, the input represents the signed integer -3 and the output represents the signed integer -1073741825.

 

Example 1:

Input: n = 00000010100101000001111010011100
Output:    964176192 (00111001011110000010100101000000)
Explanation: The input binary string 00000010100101000001111010011100 represents the unsigned integer 43261596, so return 964176192 which its binary representation is 00111001011110000010100101000000.

Example 2:

Input: n = 11111111111111111111111111111101
Output:   3221225471 (10111111111111111111111111111111)
Explanation: The input binary string 11111111111111111111111111111101 represents the unsigned integer 4294967293, so return 3221225471 which its binary representation is 10111111111111111111111111111111.

 

Constraints:

  • The input must be a binary string of length 32



solution: 


class Solution {
public:
    uint32_t reverseBits(uint32_t n) {
        uint32_t reverse =0;
        for (int i =0  ; i < 32 ; i++)
        { 
            if(1<<i & n)
                reverse = reverse | (1<<(31-i));
            
         
        }
        return  reverse;
        
    }
};

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