LeetCode in Kotlin
1318. Minimum Flips to Make a OR b Equal to c
Medium
Given 3 positives numbers a, b and c. Return the minimum flips required in some bits of a and b to make ( a OR b == c ). (bitwise OR operation).
Flip operation consists of change any single bit 1 to 0 or change the bit 0 to 1 in their binary representation.
Example 1:
Input: a = 2, b = 6, c = 5
Output: 3
Explanation: After flips a = 1 , b = 4 , c = 5 such that (a OR b == c)
Example 2:
Input: a = 4, b = 2, c = 7
Output: 1
Example 3:
Input: a = 1, b = 2, c = 3
Output: 0
Constraints:
1 <= a <= 10^91 <= b <= 10^91 <= c <= 10^9
Solution
@Suppress("NAME_SHADOWING")
class Solution {
fun minFlips(a: Int, b: Int, c: Int): Int {
var ans = 0
val or = a or b
ans += csb(or xor c)
val and = a and b
ans += csb(and and c.inv())
return ans
}
private fun csb(n: Int): Int {
var n = n
var cnt = 0
while (n > 0) {
val rsb = n and -n
n -= rsb
cnt++
}
return cnt
}
}