题目意思让你找一个最长的升序子序列
#include"bits/stdc++.h"
#define ll long long
#define pi pair<int,int>
#define inf 0x3f3f3f3f
#define _for(i,a,b) for(int i=a;i<=b;i++)
#define for_(i,a,b) for(int i=a;i<b;i++)
#define _fr(i,a,b) for(int i=a;i>=b;i--)
#define fr_(i,a,b) for(int i=a;i>b;i--)
#define IOS ios::sync_with_stdio(false),cin.tie(0),cout.tie(0)
using namespace std;
const int N = 1e5+5;
const ll mod = 1e9+7;
const double lp=1.000000011;
map<char,int>mp;
int n,x;
int a[N],b[N],c[N];
void solve(){
cin >> n;
_for(i,1,n) cin >> a[i];
_for(i,1,n) b[i]=inf;
_for(i,1,n){
int k = lower_bound(b+1,b+1+n,a[i])-b;
c[i]=k;
b[k]=a[i];
}
int ans = -inf;
_for(i,1,n){
ans = max(ans,c[i]);
}
cout << ans << endl;
}
int main()
{
IOS;
solve();
return 0;
}
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