triangles.js

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triangles.reduceTriangle(triangle)

Compute the factorial of a given number. Note that, unlike the version of this in other languages, this does not guard against imprecision or overflow.

Arguments:

  • triangle (Array.<Array.<number>>)

Returns:

number --

 1/**
 2 * Compute the factorial of a given number. Note that, unlike the version of this in other languages, this does not
 3 * guard against imprecision or overflow.
 4 * @param {Array<Array<number>>} triangle
 5 * @return {number}
 6 */
 7exports.reduceTriangle = function reduceTriangle(triangle) {
 8    centering = triangle[triangle.length - 1].length + 1;
 9    const potentialTotals = new Array(centering).fill(0);
10    const _triangle = Array.from(triangle);
11    _triangle.reverse();
12    for (const parent of _triangle) {
13        for (let i = 0; i < parent.length; i++) {
14            potentialTotals[i] = Math.max(potentialTotals[i], potentialTotals[i + 1]) + parent[i];
15        }
16    }
17    return potentialTotals[0];
18};