POJ - 2533 Longest Ordered Subsequence

标签：clu   can   inpu   pac   lan   for   let   ogr   out   

A numeric sequence of a_i is ordered if a₁ < a₂ < ... < a_N. Let the subsequence of the given numeric sequence ( a₁, a₂, ..., a_N) be any sequence ( a_i1, a_i2, ..., a_iK), where 1 <= i₁ < i₂ < ... < i_K <= N. For example, sequence (1, 7, 3, 5, 9, 4, 8) has ordered subsequences, e. g., (1, 7), (3, 4, 8) and many others. All longest ordered subsequences are of length 4, e. g., (1, 3, 5, 8).

Your program, when given the numeric sequence, must find the length of its longest ordered subsequence.Input

Output

Sample Input

7
1 7 3 5 9 4 8

Sample Output

4

f[i]=max{f[j]}+1        (j<i 且a[j]<a[i])

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 
 5 using namespace std;
 6 
 7 int a[1005],f[1005];
 8 
 9 int main()
10 {
11     int n,maxx=0;
12     scanf("%d",&n);
13     for(int i=1;i<=n;i++)
14         scanf("%d",&a[i]);
15     //memset(f,1,sizeof(int));
16     for(int i=1;i<=n;i++)
17         f[i]=1;
18     for(int i=2;i<=n;i++)
19     {
20         for(int j=1;j<i;j++)
21         {
22             if(a[i]>a[j]&&f[i]<f[j]+1)
23                 f[i]=f[j]+1;
24         }
25     //    cout<<i<<" "<<f[i]<<endl;
26     }
27     for(int i=1;i<=n;i++)
28         if(f[i]>maxx)
29             maxx=f[i];
30     printf("%d\n",maxx);
31     
32     return 0;
33 }

POJ - 2533 Longest Ordered Subsequence

标签：clu   can   inpu   pac   lan   for   let   ogr   out   

原文地址：http://www.cnblogs.com/xibeiw/p/7280250.html