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$ curl repovive.com/roadmaps/greedy-algorithms/practice-problems/broken-calculator-implementation

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$ curl repovive.com/roadmaps/greedy-algorithms/practice-problems/broken-calculator-implementation

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Broken Calculator - Implementation - Practice Problems | Greedy Algorithms | Repovive

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Greedy Algorithms8 sections · 317 units14h total

Open in Course

Broken Calculator - Implementation

The code

Here is the solution:

function brokenCalc(X, Y)
 ops := 0
 while Y > X
 if Y % 2 = 0 then
 Y := Y / 2
 else
 Y := Y + 1
 ops := ops + 1
 return ops + (X - Y)

Time: $O(\log Y)$ . Space: $O(1)$ .

Once $Y \leq X$ , you cannot halve anymore (would go below $X$ ). Just add the difference.