poj 1631 Bridging signals

#include<iostream>using namespace std;int a[40001],b[40001];int n;int find(int s,int value){    int i=0,k;    while(i<=s)    {        k=(i+s)>>1;        if(b[k]>value) s=k-1;        else i=k+1;    }    return s;}void read(){    int i,j,k;     cin>>k;    while(k--){       cin>>n;    for(i=0;i<n;i++)        cin>>a[i];      int  m=0;        b[0]=a[0];        for(i=1;i<n;i++)        { j=find(m,a[i]); b[j+1]=a[i]; if(j+1>m) m=j+1;        }    cout<<m+1<<endl;    }}int main(){    read();    return 0;}