Reverse Bits @LeetCode

PROBLEM :

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?

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SIMPLE c++ IMPLEMENTATION :
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class Solution {
public:
    uint32_t reverseBits(uint32_t n) {
        uint32_t result ;
        result=0 ;
       
        for(int i=0;i<32;i++){
            result=result<<1 ;
            result=result|(n&1) ;
            n=n>>1 ;
        }
        return result ;
    }
};

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