
ZOJ Problem Set  2074
Angel's holiday has come. Angel wants to go on a nice trip with c.x. by sea, and there are so many choices. But Angel doesn't have much money, so he can only go from one place to another with c.x. He wants to go as far as he can. We assume that there are N (1 <= n <= 30000) cities in the country. And Angel is at one of them. Every city is represented as a point (x, y), where 0 <= x, y <= 32000. Angel can start at any point and end at any point. You must find the longest distance between two points.
Author: JIANG, Yanyan Source: JIANG, Yanyan's Contest #1 