(DP) POJ 3298

Antimonotonicity

Time Limit: 2000MS		Memory Limit: 65536K
Total Submissions: 2913		Accepted: 1266

Description

I have a sequence Fred of length n comprised of integers between 1 and n inclusive. The elements of Fred is pairwise distinct. I want to find a subsequence Mary of Fred This is as long as possible and have the property that:

Mary0 > Mary1 < Mary2 > mary3 < ...

Input

The first line of input would contain a single integer T expressed in decimal with no leading zeroes. T Be is at most 50. T test cases would follow.

Each test case was contained on a. A line describing a test case is formatted as follows:

n Fred0 Fred1 Fred2 ... Fred n-1.

where n and each element of Fred are an integer expressed in decimal with no leading zeroes. No Line would have leading or trailing whitespace, and both adjacent integers on the same line would be separated by a Space. N would be is at most 30000.

Output

For each test case, output a single integer followed by a newline---the length of the longest subsequence MaryOf FredWith the desired properties.

Sample Input

45 1 2 3 4 55 5 4 3 2 15 5 1 4 2 35 2 4 1 3 5

Sample Output

1253

Source

Number of turn points +1

#include <iostream> #include <cstdio> #include <cstring> #include <cmath> #include <string > #include <algorithm> #include <cstdlib>using namespace Std;int tt,a[30005];int main () {    int n,x1,x2 , K;    scanf ("%d", &tt);    while (tt--)    {        scanf ("%d", &n);        int Ans=1;        scanf ("%d", &x1);        k=2;        for (int i=2;i<=n;i++)        {            scanf ("%d", &x2);            if (x1>x2&&k!=1)            {                k=1;                ans++;            }            if (x1<x2&&k!=2)            {                k=2;                ans++;            }            x1=x2;        }        printf ("%d\n", ans);    }    return 0;}

　　

(DP) POJ 3298