题目：

题解：

var (temp []intans [][]int
)func findSubsequences(nums []int) [][]int {ans = [][]int{}dfs(0, math.MinInt32, nums)return ans
}func dfs(cur, last int, nums []int) {if cur == len(nums) {if len(temp) >= 2 {t := make([]int, len(temp))copy(t, temp)ans = append(ans, t)}return}if nums[cur] >= last {temp = append(temp, nums[cur])dfs(cur + 1, nums[cur], nums)temp = temp[:len(temp)-1]}if nums[cur] != last {dfs(cur + 1, last, nums)}
}