LeetCode in Kotlin
371. Sum of Two Integers
Medium
Given two integers a and b, return the sum of the two integers without using the operators + and -.
Example 1:
Input: a = 1, b = 2
Output: 3
Example 2:
Input: a = 2, b = 3
Output: 5
Constraints:
-1000 <= a, b <= 1000
Solution
@Suppress("NAME_SHADOWING")
class Solution {
fun getSum(a: Int, b: Int): Int {
var a = a
var b = b
var ans = 0
var memo = 0
var exp = 0
var count = 0
while (count < 32) {
val val1 = a and 1
val val2 = b and 1
var `val` = sum(val1, val2, memo)
memo = `val` shr 1
`val` = `val` and 1
a = a shr 1
b = b shr 1
ans = ans or (`val` shl exp)
exp = plusOne(exp)
count = plusOne(count)
}
return ans
}
private fun sum(val1: Int, val2: Int, val3: Int): Int {
var count = 0
if (val1 == 1) {
count = plusOne(count)
}
if (val2 == 1) {
count = plusOne(count)
}
if (val3 == 1) {
count = plusOne(count)
}
return count
}
private fun plusOne(`val`: Int): Int {
return -`val`.inv()
}
}