32 lines
556 B
Go
32 lines
556 B
Go
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package main
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func findPeakElement(nums []int) int {
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length := len(nums)
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check := func(i int) bool {
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return (i == 0 || nums[i-1] < nums[i]) && (i == length-1 || nums[i] > nums[i+1])
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}
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if check(0) {
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return 0
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} else if check(length - 1) {
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return length - 1
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}
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left, right := 1, length-2
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for left <= right {
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mid := (left + right) / 2
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if check(mid) {
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return mid
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} else if nums[mid] < nums[mid-1] {
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right = mid - 1
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} else if nums[mid] < nums[mid+1] {
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left = mid + 1
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}
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}
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panic("unreachable: peak element is guaranteed")
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}
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