codeforces 261D Maxim and Increasing Subsequence(树状数组优化最长上升子列)

题目链接：http://codeforces.com/problemset/problem/261/D

题意：最长上升子列。

思路:树状数组优化求最长上升子列。

#include <iostream>
#include <cstdio>
#include <string.h>
#include <algorithm>
#include <cmath>
#include <vector>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <map>

#define max(x,y) ((x)>(y)?(x):(y))
#define min(x,y) ((x)<(y)?(x):(y))
#define abs(x) ((x)>=0?(x):-(x))
#define i64 long long
#define u32 unsigned int
#define u64 unsigned long long
#define clr(x,y) memset(x,y,sizeof(x))
#define CLR(x) x.clear()
#define ph(x) push(x)
#define pb(x) push_back(x)
#define Len(x) x.length()
#define SZ(x) x.size()
#define PI acos(-1.0)
#define sqr(x) ((x)*(x))

#define FOR0(i,x) for(i=0;i<x;i++)
#define FOR1(i,x) for(i=1;i<=x;i++)
#define FOR(i,a,b) for(i=a;i<=b;i++)
#define DOW0(i,x) for(i=x;i>=0;i--)
#define DOW1(i,x) for(i=x;i>=1;i--)
#define DOW(i,a,b) for(i=a;i>=b;i--)
using namespace std;


int K,n,maxb,t;
int a[100005],c[100005],ans[100005];

void update(int x,int d)
{
    while(x<=maxb)
    {
        if(d>c[x]) c[x]=d;
        x+=x&-x;
    }
}

int get(int x)
{
    int ans=0;
    while(x>0)
    {
        ans=max(ans,c[x]);
        x-=x&-x;
    }
    return ans;
}

int cal()
{
    clr(c,0);
    clr(ans,0);
    int i,j,k;
    for(i=1;i<=t;i++) for(j=1;j<=n;j++)
    {
        k=get(a[j]-1)+1;
        if(k>ans[j])
        {
            ans[j]=k;
            update(a[j],k);
        }
    }
    return *max_element(ans+1,ans+n+1);
}

int main()
{
    scanf("%d%d%d%d",&K,&n,&maxb,&t);
    int i;
    while(K--)
    {
        for(i=1;i<=n;i++) scanf("%d",&a[i]);
        if(t>=maxb)
        {
            sort(a+1,a+n+1);
            printf("%d\n",unique(a+1,a+n+1)-(a+1));
            continue;
        }
        printf("%d\n",cal());
    }
    return 0;
}