We have a group of N items (represented by integers from 1 to N), and we know that there is some total order defined for these items. You may assume that no two elements will be equal (for all a, b: a<b or b<a). However, it is expensive to compare two items. Your task is to make a number of comparisons, and then output the sorted order. The cost of determining if a < b is given by the bth integer of element a of costs (space delimited), which is the same as the ath integer of element b. Naturally, you will be judged on the total cost of the comparisons you make before outputting the sorted order. If your order is incorrect, you will receive a 0. Otherwise, your score will be opt/cost, where opt is the best cost anyone has achieved and cost is the total cost of the comparisons you make (so your score for a test case will be between 0 and 1). Your score for the problem will simply be the sum of your scores for the individual test cases.
標簽:
represented
integers
group
items
上傳時間:
2016-01-17
上傳用戶:jeffery
問題描述
序列Z=<B,C,D,B>是序列X=<A,B,C,B,D,A,B>的子序列,相應的遞增下標序列為<2,3,5,7>。
一般地,給定一個序列X=<x1,x2,…,xm>,則另一個序列Z=<z1,z2,…,zk>是X的子序列,是指存在一個嚴格遞增的下標序列〈i1,i2,…,ik〉使得對于所有j=1,2,…,k使Z中第j個元素zj與X中第ij個元素相同。
給定2個序列X和Y,當另一序列Z既是X的子序列又是Y的子序列時,稱Z是序列X和Y的公共子序列。
你的任務是:給定2個序列X、Y,求X和Y的最長公共子序列Z。
標簽:
lt
序列
上傳時間:
2014-01-25
上傳用戶:netwolf