easy

1.
FrogJmp

Count minimal number of jumps from position X to Y.
100%

100%

100%

Task description

A small frog wants to get to the other side of the road. The frog is currently located at position X and wants to get to a position greater than or equal to Y. The small frog always jumps a fixed distance, D.

Count the minimal number of jumps that the small frog must perform to reach its target.

Write a function:

function solution($X, $Y, $D);

that, given three integers X, Y and D, returns the minimal number of jumps from position X to a position equal to or greater than Y.

For example, given:

the function should return 3, because the frog will be positioned as follows:

- after the first jump, at position 10 + 30 = 40
- after the second jump, at position 10 + 30 + 30 = 70
- after the third jump, at position 10 + 30 + 30 + 30 = 100

Write an ** efficient** algorithm for the following assumptions:

- X, Y and D are integers within the range [1..1,000,000,000];
- X ≤ Y.

Copyright 2009–2018 by Codility Limited. All Rights Reserved. Unauthorized copying, publication or disclosure prohibited.

Solution

Programming language used PHP

Total time used 4 minutes

Effective time used 4 minutes

Notes
*not defined yet*

Task timeline

Code: 19:03:11 UTC,
php,
verify,
result: **Failed**

Analysis

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**Example tests**

1.

0.012 s

stderr:

Invalid result type, int expected.

Code: 19:04:16 UTC,
php,
verify,
result: **Failed**

Analysis

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**Example tests**

1.

0.011 s

stderr:

PHP Fatal error: Call to undefined function int_val() in func.php on line 7 Fatal error: Call to undefined function int_val() in func.php on line 7

Code: 19:04:23 UTC,
php,
verify,
result: **Failed**

Analysis

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**Example tests**

1.

0.012 s

Code: 19:04:34 UTC,
php,
verify,
result: **Failed**

Analysis

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**Example tests**

1.

0.021 s

Code: 19:04:49 UTC,
php,
verify,
result: **Failed**

Analysis

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**Example tests**

1.

0.021 s

Code: 19:04:58 UTC,
php,
verify,
result: **Failed**

Analysis

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**Example tests**

1.

0.011 s

Code: 19:05:14 UTC,
php,
verify,
result: **Passed**

Analysis

Code: 19:05:46 UTC,
php,
verify,
result: **Passed**

Analysis

Code: 19:05:48 UTC,
php,
final,
score: **
100
**

Analysis summary

The solution obtained perfect score.

Analysis

Detected time complexity:

**O(1)**

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**Correctness tests**

1.

0.020 s

2.

0.020 s

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0.020 s

2.

0.021 s

1.

0.021 s

2.

0.021 s

1.

0.021 s