# Leetcode: Broken Calculator

Broken Calculator

Similar Problems:

On a broken calculator that has a number showing on its display, we can perform two operations:

Double: Multiply the number on the display by 2, or;
Decrement: Subtract 1 from the number on the display.
Initially, the calculator is displaying the number X.

Return the minimum number of operations needed to display the number Y.

Example 1:

```Input: X = 2, Y = 3
Output: 2
Explanation: Use double operation and then decrement operation {2 -> 4 -> 3}.
```

Example 2:

```Input: X = 5, Y = 8
Output: 2
Explanation: Use decrement and then double {5 -> 4 -> 8}.
```

Example 3:

```Input: X = 3, Y = 10
Output: 3
Explanation:  Use double, decrement and double {3 -> 6 -> 5 -> 10}.
```

Example 4:

```Input: X = 1024, Y = 1
Output: 1023
Explanation: Use decrement operations 1023 times.
```

Note:

1. 1 <= X <= 10^9
2. 1 <= Y <= 10^9

Github: code.dennyzhang.com

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• Solution: XXX

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Key Observations:

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Walk Through Testdata

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