Commit 358b199

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chore: Merge pull request #789 from devcer/master

Added Maximum product of 3 numbers in an array

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	`1`	`+/**`
	`2`	`+ * Given an array of numbers, return the maximum product`
	`3`	`+ * of 3 numbers from the array`
	`4`	`+ * https://wsvincent.com/javascript-three-sum-highest-product-of-three-numbers/`
	`5`	`+ * @param {number[]} arrayItems`
	`6`	`+ * @returns number`
	`7`	`+ */`
	`8`	`+export function maxProductOfThree(arrayItems) {`
	`9`	`+ // if size is less than 3, no triplet exists`
	`10`	`+ let n = arrayItems.length`
	`11`	`+ if (n < 3) throw new Error('Triplet cannot exist with the given array')`
	`12`	`+ let max1 = arrayItems[0],`
	`13`	`+ max2 = -1,`
	`14`	`+ max3 = -1,`
	`15`	`+ min1 = arrayItems[0],`
	`16`	`+ min2 = -1`
	`17`	`+ for (let i = 1; i < n; i++) {`
	`18`	`+ if (arrayItems[i] > max1) {`
	`19`	`+ max3 = max2`
	`20`	`+ max2 = max1`
	`21`	`+ max1 = arrayItems[i]`
	`22`	`+ } else if (max2 === -1 \|\| arrayItems[i] > max2) {`
	`23`	`+ max3 = max2`
	`24`	`+ max2 = arrayItems[i]`
	`25`	`+ } else if (max3 === -1 \|\| arrayItems[i] > max3) {`
	`26`	`+ max3 = arrayItems[i]`
	`27`	`+ }`
	`28`	`+ if (arrayItems[i] < min1) {`
	`29`	`+ min2 = min1`
	`30`	`+ min1 = arrayItems[i]`
	`31`	`+ } else if (min2 === -1 \|\| arrayItems[i] < min2) {`
	`32`	`+ min2 = arrayItems[i]`
	`33`	`+ }`
	`34`	`+ }`
	`35`	`+ let prod1 = max1 * max2 * max3,`
	`36`	`+ prod2 = max1 * min1 * min2`
	`37`	`+ return Math.max(prod1, prod2)`
	`38`	`+}`

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	`1`	`+import { maxProductOfThree } from '../MaxProductOfThree'`
	`2`	`+`
	`3`	`+describe('MaxProductOfThree', () => {`
	`4`	`+ it('expects to throw error for array with only 2 numbers', () => {`
	`5`	`+ expect(() => {`
	`6`	`+ maxProductOfThree([1, 3])`
	`7`	`+ }).toThrow('Triplet cannot exist with the given array')`
	`8`	`+ })`
	`9`	`+`
	`10`	`+ it('expects to return 300 as the maximum product', () => {`
	`11`	`+ expect(maxProductOfThree([10, 6, 5, 3, 1, -10])).toBe(300)`
	`12`	`+ })`
	`13`	`+`
	`14`	`+ it('expects to return 300 as the maximum product', () => {`
	`15`	`+ expect(maxProductOfThree([10, -6, 5, 3, 1, -10])).toBe(600)`
	`16`	`+ })`
	`17`	`+})`

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