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algorithm: Log2 using bitwise operations (#1132)

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	`1`	`+/**`
	`2`	`+ * https://handwiki.org/wiki/Binary_logarithm`
	`3`	`+ * Approximate log2 using only bitwise operators`
	`4`	`+ * @param {number} n`
	`5`	`+ * @returns {number} Log2 approximation equal to floor(log2(n))`
	`6`	`+ */`
	`7`	`+export const logTwo = (n) => {`
	`8`	`+ let result = 0`
	`9`	`+ while (n >> 1) {`
	`10`	`+ n >>= 1`
	`11`	`+ result++`
	`12`	`+ }`
	`13`	`+ return result`
	`14`	`+}`

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	`1`	`+import { logTwo } from '../LogTwo'`
	`2`	`+`
	`3`	`+for (let i = 1; i < 100; i++) {`
	`4`	`+ test('log2(' + i + ')', () => {`
	`5`	`+ expect(logTwo(i)).toBe(Math.floor(Math.log2(i)))`
	`6`	`+ })`
	`7`	`+}`

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