题目：

题解：

var (
    temp []int
    ans [][]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)
    }
}