#Given an array and a value, find if there is a triplet in array whose sum is equal to the given value. #Time-complexity: O(n^2),Auxiliary-space:O(1) #Algorithm:Sort,fix element then search in the array using two pointers left and right def search_triplet(a,key) len=a.length a.sort! #Any sorting technique can be chosen for i in 0...len-1 sum= key-a[i] left=i+1 right=len-1 while(leftsum right-=1 else left+=1 end end end return -1 end search_triplet([12, 3, 4, 1, 6, 9],25) # => [4, 9, 12]