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Create: 0034-find-first-and-last-position-of-element-in-sorted-array.cpp

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	`1`	`+/*`
	`2`	`+ Given an array of integers nums sorted in non-decreasing order, find the starting and ending position of a given target value.`
	`3`	`+ Ex. nums = [5,7,7,8,8,10], target = 8 -> [3, 4] (start position is 3, end position is 4)`
	`4`	`+`
	`5`	`+ Use binary search, firstly binary search left endpoint, then binary search right endpoint.`
	`6`	`+`
	`7`	`+ Time: O(log n)`
	`8`	`+ Space: O(1)`
	`9`	`+*/`
	`10`	`+`
	`11`	`+classSolution {`
	`12`	`+public:`
	`13`	`+ vector<int>searchRange(vector<int>& nums,int target) {`
	`14`	`+if (nums.empty())return {-1, -1};`
	`15`	`+int l =0, r = nums.size() -1;`
	`16`	`+while (l < r) {`
	`17`	`+int mid = l + r >>1;`
	`18`	`+if (nums[mid] >= target) r = mid;`
	`19`	`+else l = mid +1;`
	`20`	`+ }`
	`21`	`+if (nums[l] != target)return {-1, -1};`
	`22`	`+int left = l;`
	`23`	`+`
	`24`	`+ l =0, r = nums.size() -1;`
	`25`	`+while (l < r) {`
	`26`	`+int mid = l + r +1ll >>1;`
	`27`	`+if (nums[mid] <= target) l = mid;`
	`28`	`+else r = mid -1;`
	`29`	`+ }`
	`30`	`+return {left, r};`
	`31`	`+ }`
	`32`	`+};`

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