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merge: fixes: #{} (#853)

* fixes: #{} * fixes : ISSUE#795 * Fixed ISSUE:795 * Fixed : ISSUE:795 * Fixed ISSUE : 795 * Fixed ISSUE : 795

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	`1`	`+/*`
	`2`	`+ * Author: Mohit Kumar`
	`3`	`+ * Fedwick Tree Implementation in JavaScript`
	`4`	`+ * Fedwick Tree Implementation for finding prefix sum.`
	`5`	`+*/`
	`6`	`+`
	`7`	`+class FenwickTree {`
	`8`	`+ constructor (feneickArray, array, n) {`
	`9`	`+ for (let i = 1; i <= n; i++) {`
	`10`	`+ feneickArray[i] = 0`
	`11`	`+ }`
	`12`	`+ for (let i = 0; i < n; i++) {`
	`13`	`+ this.update(feneickArray, n, i, array[i])`
	`14`	`+ }`
	`15`	`+ }`
	`16`	`+`
	`17`	`+ update (feneickArray, n, index, value) {`
	`18`	`+ index = index + 1`
	`19`	`+ while (index <= n) {`
	`20`	`+ feneickArray[index] += value`
	`21`	`+ index += index & (-index)`
	`22`	`+ }`
	`23`	`+ }`
	`24`	`+`
	`25`	`+ getPrefixSum (feneickArray, index) {`
	`26`	`+ let currSum = 0`
	`27`	`+ index = index + 1`
	`28`	`+ while (index > 0) {`
	`29`	`+ currSum += feneickArray[index]`
	`30`	`+ index -= index & (-index)`
	`31`	`+ }`
	`32`	`+`
	`33`	`+ return currSum`
	`34`	`+ }`
	`35`	`+}`
	`36`	`+export { FenwickTree }`

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	`1`	`+import { FenwickTree } from '../FenwickTree'`
	`2`	`+`
	`3`	`+describe('Fenwick Tree Implementation', () => {`
	`4`	`+ const fenwickArray = new Array(1000)`
	`5`	`+ const array = [3, 2, 0, 6, 5, -1, 2]`
	`6`	`+ const length = array.length`
	`7`	`+`
	`8`	`+ const fenwickTree = new FenwickTree(fenwickArray, array, length)`
	`9`	`+`
	`10`	`+ it('Fenwick Tree - Prefix sum of array', () => {`
	`11`	`+ const prefixSum = fenwickTree.getPrefixSum(fenwickArray, 6)`
	`12`	`+ expect(prefixSum).toBe(23)`
	`13`	`+ })`
	`14`	`+`
	`15`	`+ array[2] += 6`
	`16`	`+ fenwickTree.update(fenwickArray, length, 2, 6)`
	`17`	`+`
	`18`	`+ it('Fenwick Tree - Prefix sum of Updated array', () => {`
	`19`	`+ const prefixSum = fenwickTree.getPrefixSum(fenwickArray, 6)`
	`20`	`+ expect(prefixSum).toBe(23)`
	`21`	`+ })`
	`22`	`+})`

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