[LeetCode 201] Bitwise AND of Numbers Range
Given a range [m, n] where 0 <= m <= n <= 2147483647, return the bitwise AND of all numbers in this range, inclusive.
For example, given the range [5, 7], you should return 4.
solution:
bit manipulation, calculate common 1 prefix between m and n;
For example, given the range [5, 7], you should return 4.
solution:
bit manipulation, calculate common 1 prefix between m and n;
public int rangeBitwiseAnd(int m, int n) {
if(m == n) return m;
int bit = 0;
while(m!=n) {
m=m>>1;
n=n>>1;
bit++;
}
return m<<bit;
}