Hello, what is the difference between h1? which is this one and h2 below?

This is h2, what is the difference. Can I make up the difference?

Given an array nums of n integers, return an array of all the unique quadrupletes [nums[a], nums[b], nums[c], nums[d]] such that: 0<= a,b,c,d,n, a,b,c, and d are distinct. nums[a]+nums[b]+nums[c]+nums[d] ==target you may return the answer in any order.