Bitwise AND of Numbers Range
Problem Statement - link #
Given two integers left and right that represent the range [left, right], return the bitwise AND of all numbers in this range, inclusive.
Examples #
Example 1:
Input: left = 5, right = 7
Output: 4
Example 2:
Input: left = 0, right = 0
Output: 0
Example 3:
Input: left = 1, right = 2147483647
Output: 0
Constraints #
0 <= left <= right <= 2^31 - 1
Solutions #
class Solution {
public:
int rangeBitwiseAnd(int left, int right) {
if(left == 0 || right == 0) return 0;
if(left == right) return left;
if(left == right-1) return left&right;
if((int)log2(left) != (int)log2(right)) return 0;
else{
int ans = left;
for(int i=left+1;i<=right;i++)
ans&=i;
return ans;
}
}
};