mirror of
https://github.com/TheAlgorithms/JavaScript.git
synced 2025-07-04 15:39:42 +08:00
86d333ee94
* chore: Switch to Node 20 + Vitest * chore: migrate to vitest mock functions * chore: code style (switch to prettier) * test: re-enable long-running test Seems the switch to Node 20 and Vitest has vastly improved the code's and / or the test's runtime! see #1193 * chore: code style * chore: fix failing tests * Updated Documentation in README.md * Update contribution guidelines to state usage of Prettier * fix: set prettier printWidth back to 80 * chore: apply updated code style automatically * fix: set prettier line endings to lf again * chore: apply updated code style automatically --------- Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com> Co-authored-by: Lars Müller <34514239+appgurueu@users.noreply.github.com>
20 lines
643 B
JavaScript
20 lines
643 B
JavaScript
// https://projecteuler.net/problem=15
|
||
/* Starting in the top left corner of a 2×2 grid, and only being able to move to
|
||
the right and down, there are exactly 6 routes to the bottom right corner.
|
||
How many such routes are there through a 20×20 grid?
|
||
*/
|
||
|
||
// A lattice path is composed of horizontal and vertical lines that pass through lattice points.
|
||
|
||
export const latticePath = (gridSize) => {
|
||
let paths
|
||
for (let i = 1, paths = 1; i <= gridSize; i++) {
|
||
paths = (paths * (gridSize + i)) / i
|
||
}
|
||
// The total number of paths can be found using the binomial coefficient (b+a)/a.
|
||
return paths
|
||
}
|
||
|
||
// > latticePath(20))
|
||
// 137846528820
|