\(O(n \log n)\)的求最长上升子序列
法一：二分
int LIS(){
int b[MAXN], top = 0, a[MAXN];
b[0] = -1;
for(int i = 1; i <= n; i++){
if(a[i] > b[top]){
top++, b[top] = a[i];
}else{
int l = 1, r = top;
while(l < r){ // 二分，O(log n)
int u = (l + r) >> 1;
if(a[i] > b[u]){
l = u + 1;
}else{
r = u - 1;
}
}
b[l] = a[i];
}
}
return top;
}
法二：线段树
略