预处理 + 二分法
var findMin = function(nums) {
let n = nums.length
if (n - 1 < 0) return -1
let left = 0
let right = n - 1
while ( right > 0 && nums[0] === nums[right]) right --
if (nums[right] >= nums[0]) return nums[0]
while (left < right) {
let mid = left + right >> 1
if (nums[mid] < nums[0]) {
right = mid
} else {
left = mid + 1
}
}
return nums[right]
};