leedcode 191 Hamming Weight

191.

For example, the 32-bit integer ’11‘ has binary representation 00000000000000000000000000001011, so the function should return 3.

Java code

int hammingweight(int n) //因为是32位，所以n要看做无符号整数

{

　　int sum =0;　　

　　while(n!=0){

　　　　if(n&1==1)

　　　　sum++;

　　　　n>>>1; //n无符号右移一位，即左边补0；注意与>>的区别，>>是有符号右移，例 1001>>1=1000;而1001>>>1=0000

　　}

　　return sum;

}

时间： 2024-10-14 11:20:44

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