P1816树状数组做法求调

#include <bits/stdc++.h>
#define int long long
#define lowbit(x) (x)&-(x)
using namespace std;
int n,m,h[100005],a[100005];
void add(int pos,int v)
{
	while(pos<=n)
	{
		if(v>=h[pos]) return ;
		h[pos]=min(h[pos],v);
		pos+=lowbit(pos);
	}
}
int query(int l,int r)
{
	int ans=INT_MAX;
	while(r>=l)
	{
		ans=min(ans,a[r--]);
		while(r-lowbit(r)>l)
		{
			ans=min(ans,h[r]);
			r-=lowbit(r);
		}
	}
	return ans;
}
signed main()
{
	ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	cin>>n>>m;
	for(int i=1;i<=n;++i)
	{
		cin>>a[i];
		add(i,a[i]);
	}
	int l,r;
	while(m--)
	{
		cin>>l>>r;
		cout<<query(l,r)<<' ';
	}
	return 0;
}