Problem C. Islands Travel

Source

Problem

时间限制:10000ms

单点时限:1000ms

内存限制:256MB

描述

There are N islands on a planet whose coordinates are (X1, Y1), (X2, Y2), (X3,
Y3) …, (XN, YN). You starts at the 1st island (X1, Y1) and your destination
is the n-th island (XN, YN). Travelling between i-th and j-th islands will
cost you min{|Xi-Xj|, |Yi-Yj|} (|a| denotes the absolute value of a. min{a, b}
denotes the smaller value between a and b) gold coins. You want to know what
is the minimum cost to travel from the 1st island to the n-th island.

输入

Line 1: an integer N.

Line 2~N+1: each line contains two integers Xi and Yi.

For 40% data, N<=1000，0<=Xi,Yi<=100000.

For 100% data, N<=100000，0<=Xi,Yi<=1000000000.

输出

Output the minimum cost.

样例输入

  1. 3
  2. 2 2
  3. 1 7
  4. 7 6

样例输出

  1. 2