LeetCode in Kotlin
991. Broken Calculator
Medium
There is a broken calculator that has the integer startValue on its display initially. In one operation, you can:
- multiply the number on display by
2, or - subtract
1from the number on display.
Given two integers startValue and target, return the minimum number of operations needed to display target on the calculator.
Example 1:
Input: startValue = 2, target = 3
Output: 2
Explanation: Use double operation and then decrement operation {2 -> 4 -> 3}.
Example 2:
Input: startValue = 5, target = 8
Output: 2
Explanation: Use decrement and then double {5 -> 4 -> 8}.
Example 3:
Input: startValue = 3, target = 10
Output: 3
Explanation: Use double, decrement and double {3 -> 6 -> 5 -> 10}.
Constraints:
1 <= startValue, target <= 109
Solution
@Suppress("NAME_SHADOWING")
class Solution {
fun brokenCalc(startValue: Int, target: Int): Int {
var target = target
var result = 0
while (startValue != target) {
if (target > startValue && target % 2 != 0) {
target += 1
result++
} else if (target > startValue) {
target /= 2
result++
} else {
result += startValue - target
break
}
}
return result
}
}