Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

[Hacker Rank]: Project Euler #2: Even Fibonacci numbers solved ✓ #489

Merged
merged 1 commit into from
Sep 27, 2024
Merged
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
47 changes: 47 additions & 0 deletions docs/hackerrank/projecteuler/euler002.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,47 @@
# [Even Fibonacci numbers](https://www.hackerrank.com/contests/projecteuler/challenges/euler002)

- Difficulty: #easy
- Category: #ProjectEuler+

Each new term in the Fibonacci sequence is generated by adding the previous two terms.
By starting with $ 1 $ and $ 2 $, the first $ 10 $ terms will be:

$$ 1, 2, 3, 5, 8, 13, 21, 34, 55, 89 $$

By considering the terms in the Fibonacci sequence whose values do not exceed
$ N $, find the sum of the even-valued terms.

## Input Format

First line contains $ T $ that denotes the number of test cases. This is
followed by $ T $ lines, each containing an integer, $ N $.

## Constraints

- $ 1 \leq T \leq 10^5 $
- $ 10 \leq N \leq 4 × 10^{16} $

## Output Format

Print the required answer for each test case.

## Sample Input 0

```text
2
10
100
```

## Sample Output 0

```text
10
44
```

## Explanation 0

- For $ N = 10 $, we have $ \{2, 8\} $, sum is $ 10 $.

- For $ N = 100 $, we have $ \{2, 8, 34 \} $, sum is $ 44 $.
19 changes: 19 additions & 0 deletions src/hackerrank/projecteuler/euler002.test.ts
Original file line number Diff line number Diff line change
@@ -0,0 +1,19 @@
import { describe, expect, it } from '@jest/globals';
import { logger as console } from '../../logger';

import { euler002 } from './euler002';

import TEST_CASES from './euler002.testcases.json';

describe('euler002', () => {
it('euler002 JSON Test cases', () => {
expect.assertions(2);

TEST_CASES.forEach((test) => {
const calculated = euler002(test.n);
console.log(`euler002(${test.n}) solution found: ${test.expected}`);

expect(`${calculated}`).toBe(`${test.expected}`);
});
});
});
4 changes: 4 additions & 0 deletions src/hackerrank/projecteuler/euler002.testcases.json
Original file line number Diff line number Diff line change
@@ -0,0 +1,4 @@
[
{ "n": 10, "expected": 10 },
{ "n": 100, "expected": 44 }
]
27 changes: 27 additions & 0 deletions src/hackerrank/projecteuler/euler002.ts
Original file line number Diff line number Diff line change
@@ -0,0 +1,27 @@
/**
* @link Problem definition [[docs/hackerrank/projecteuler/euler002.md]]
*/

export function fiboEvenSum(n: bigint): bigint {
let fibo1 = 1n;
let fibo2 = 1n;
let total = 0n;

while (fibo1 + fibo2 < n) {
const fibo = fibo1 + fibo2;
fibo1 = fibo2;
fibo2 = fibo;

if (fibo % 2n === 0n) {
total += fibo;
}
}

return total;
}

export function euler002(n: number): bigint {
return fiboEvenSum(BigInt(n));
}

export default { euler002 };