[HDU

来源:互联网 发布:java shiro 权限控制 编辑:程序博客网 时间:2024/06/04 00:22

Link:http://acm.hdu.edu.cn/showproblem.php?pid=5773

Problem Description

?? gets an sequence S with n intergers(0 < n <= 100000,0<= S[i] <= 1000000).?? has a magic so that he can change 0 to any interger(He does not need to change all 0 to the same interger).?? wants you to help him to find out the length of the longest increasing (strictly) subsequence he can get.

Input

The first line contains an interger T,denoting the number of the test cases.(T <= 10)
For each case,the first line contains an interger n,which is the length of the array s.
The next line contains n intergers separated by a single space, denote each number in S.

Output

For each test case, output one line containing “Case #x: y”(without quotes), where x is the test case number(starting from 1) and y is the length of the longest increasing subsequence he can get.

Sample Input

272 0 2 1 2 0 561 2 3 3 0 0

Sample Output

Case #1: 5Case #2: 5

Hint

In the first case,you can change the second 0 to 3.So the longest increasing subsequence is 0 1 2 3 5.

题解:

题意就是0可以变成任何值 求LIS

步骤:

  1. b[i]==0时记下i之前0的个数, 记为k
  2. b[i]!=0时存在新数组a里,a[j++]=b[i]-k;
  3. ans = 新数组a的LIS+k

对于第2点,例如当数列为 1 0 0 0 2 时,LIS= 4(1 2 3 4 2),1、2 之间没有整数,2减去它前面0的个数为-1, (1 -1)的LIS=1,再加3可得LIS=4

Code:

#include<iostream>#include<algorithm>#include<cstdio>#include<cstdlib>#include<cmath>#include<cstring>#include<queue>#include<stack>#define INF 0x3f3f3fusing namespace std;const int maxn=1e6+10;int a[maxn];int dp[maxn];int b[maxn];int main(){    int t,n,k,c=1;    scanf("%d",&t);    while(t--)    {        k=0;        int j=0;        scanf("%d",&n);        for(int i=0;i<n;i++)        {            scanf("%d",&b[i]);            dp[i]=INF;            if(b[i]==0)            {                k++;            }            else            {                b[i]-=k;                a[j++]=b[i];            }           }        for(int i=0;i<j;i++)            *lower_bound(dp,dp+n,a[i])=a[i];        printf("Case #%d: %d\n",c++,lower_bound(dp,dp+n,INF)-dp+k);    }return 0;}
原创粉丝点击