[LeetCode]Reverse Bits

Posted 2020-06-08

190. Reverse Bits

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).

 

太水了，就是简单的位运算，只要想到一个简单的策略就好了

Ps.由于java对无符号数支持不好，所以这里就用c水过就好啦。

#include <stdio.h>
#include <inttypes.h>
uint32_t reverseBits(uint32_t n) {
    uint32_t ret = 0;
    for(int i=0 ;i<=31;i++){
       ret+=((n & (1<<i))>>i)<< (31-i);
    }
    return ret;
}

int main(){
   uint32_t n;
   scanf("%d",&n);
   printf("%u",reverseBits(n));
   return 0;    
}