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Counting Bits

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	`1`	`+'''Leetcode- https://leetcode.com/problems/counting-bits/ '''`
	`2`	`+'''`
	`3`	`+Given an integer n, return an array ans of length n + 1 such that for each i (0 <= i <= n), ans[i] is the number of 1's in the binary representation of i.`
	`4`	`+`
	`5`	`+Example 1:`
	`6`	`+`
	`7`	`+Input: n = 2`
	`8`	`+Output: [0,1,1]`
	`9`	`+Explanation:`
	`10`	`+0 --> 0`
	`11`	`+1 --> 1`
	`12`	`+2 --> 10`
	`13`	`+'''`
	`14`	`+`
	`15`	`+# Bit manipulation approach`
	`16`	`+def countBits(self, n):`
	`17`	`+ ans = []`
	`18`	`+ for i in range(n+1):`
	`19`	`+ cur = 0`
	`20`	`+ while i:`
	`21`	`+ cur += i & 1`
	`22`	`+ i >>= 1`
	`23`	`+ ans.append(cur)`
	`24`	`+ return ans`
	`25`	`+`
	`26`	`+# T:O(NlogN)`
	`27`	`+# S:O(N)`
	`28`	`+`
	`29`	`+#DP way`
	`30`	`+def countBits(self, n):`
	`31`	`+ dp = [0]*(n+1)`
	`32`	`+ offset = 0`
	`33`	`+`
	`34`	`+ for i in range(1,n+1):`
	`35`	`+ if offset*2 == i:`
	`36`	`+ offset = i`
	`37`	`+ dp[i] = 1 + dp[i-offset]`
	`38`	`+ return dp`
	`39`	`+`
	`40`	`+# T:O(N)`
	`41`	`+# S:O(N)`

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`@@ -26,4 +26,5 @@ Check the notes for the explaination - [Notes](https://stingy-shallot-4ea.notion`
`26`	`26`	`- [x] [Climbing Stairs](Dynamic-Programming/70-Climbing-Stairs.py)`
`27`	`27`	`- [x] [Maximum Subarray](Dynamic-Programming/53-maximum-subarray.py)`
`28`	`28`	`- [x] [Range Sum Query - Immutable](Dynamic-Programming/303-Range-Sum-Query-Immutable.py)`
	`29`	`+ - [x] [Counting Bits](Dynamic-Programming/338-Counting-Bits.py)`
`29`	`30`

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