Given a vector vec, create a v-shaped vector as shown below: vec = [ 10 2 3 89 5 7 90 0 12]

Output vector = [90 89 12 10 7 5 3 2 0 0 2 3 5 7 10 12 89 90]

Here, all the elements of input vector are repeated in output vector, however first half part of the output vector is in descending order and rest is in ascending order. Once such output vector is plotted, it will show a v-shape on the graph. Do not use builtin sort function