1st approachclass Solution {public: vector> subsets(vector& nums) { int n = nums.size(); int tablesize = pow(2,n); vector> res; vector arr(tablesize); for (int i = 0; i solclass Solution {public: vector> subsets(vector& nums) { int n = nums.size(); int tablesize = pow(2, n); // 2^n possible subsets vector> res(tablesize); // Initial..