def find(nums, k): dic = {} res = [] for i in nums: if i not in dic: dic[k+i]=i else: res.append([dic[i],i]) return res nums = [x for x in range(1,11)] print find(nums, 3)

Assuming no duplicates, sort an array, iterate through it and find a number a[i]+k, code: public void find(int[]a, int k){ if(a==null||a.length==0)return; if(k == 0){ //since the elements are distinct return; } Arrays.sort(a); for(int i = 0; i =0){ System.out.println(a[i] + " " + a[idx]); } } }