# 1498. Number of Subsequences That Satisfy the Given Sum Condition """ given an array of integers 'nums' and an integer 'target' return the numbe of non-empty subsequences of 'nums' such that the sum of the minimum and maximum element on it is less or equal to 'target'. return modulo 10^9+7 """ class Solution(object): def numSubseq(self, nums, target): """ :type nums: List[int] :type target: int :rtype: int """ pows, mod = [1], 10**9 + 7 nums.sort() for i in range(1, len(nums)): pows.append((pows[-1] << 1) % mod) ans, l, r = 0, 0, len(nums) - 1 while l <= r: if nums[l] + nums[r] > target: r -= 1 continue ans = (ans + pows[r - l]) % mod l += 1 return ans if __name__ == "__main__": obj = Solution() print(obj.numSubseq(nums=[3, 5, 6, 7], target=9)) print(obj.numSubseq(nums=[3, 3, 6, 8], target=10)) print(obj.numSubseq(nums=[2, 3, 3, 4, 6, 7], target=12))