Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand.
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| (i.e., [0,1,2,4,5,6,7] might become [4,5,6,7,0,1,2]).
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Find the minimum element.
You may assume no duplicate exists in the array.
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| Example 1:
Input: [3,4,5,1,2]
Output: 1
Example 2:
Input: [4,5,6,7,0,1,2]
Output: 0
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Notes
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| - no dups
- rotation pivot in not known?
- sorted in ascending order
- min should be at pivot
- peak just before pivot if pivot is not 0
1, 3, 5 --> pivot is at 0 - min is 1
56781234 --> min is 1
min
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test 6
test 7
test 8
test 1 ---> min is 1
break
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The following is a O(n) solution
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| int findMin(vector<int>& nums) {
int min = nums[0];
for (int i = 0; i < nums.size(); i++) {
if ((i < nums.size() - 1) &&
nums[i] > nums[i+1]) {
min = nums[i+1];
break;
}
}
return min;
}
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There is a O(logn) solution that uses binary search!