5. Two friends, who live in the (far away) cities of Shihkiachwang and Chengdu, decided to meet during the coming Christmas vacation. They can only travel by bus and they must take a different bus (poesibly at a different cost) between any two neighboring cities. To split the travel cost among each other, and because each of them wants to go to a new place, the two friends decided to meet halfway or just somewhere between Shihkiachwang and Chengdu, The total travel cost would (therefore) be the maximum amount that any of the two friends pays. You are asked to give a most-efficient algorithm that takes the cost of travel between any two adjacent cities as input and finds the minimum cost