算法练习LeetCode初级算法之其他

• 位1的个数

• 解法一：

  class Solution {

  // you need to treat n as an unsigned value

  public int hammingWeight(int n) {

      return Integer.bitCount(n);

  }

  }

• 解法二：

  记住一点，前面的零没用的不要！！

  class Solution {

  // you need to treat n as an unsigned value

  public int hammingWeight(int n) {

      int k=0;

      while (n>0) {

              if (n%2==1) {

                  k++;

              }

              n/=2;

          }

      return k;

  }

  }

• 汉明距离

  class Solution {

  public int hammingDistance(int x, int y) {

  int k=0;

  while (x>0||y>0) {

              if (x%2!=y%2) {

                  k++;

              }

              x/=2;

              y/=2;

          }

  return k;

  }

  }