直接线段树维护[l,r]的点能炸到的左端点和右端点，反着跑7次洛谷loj全过???

#include<bits/stdc++.h>
#define int long long
#define maxn 500005
using namespace std;
int n,x[maxn],ran[maxn],l[maxn],r[maxn],maxx,ans;
struct seg{int lef,rig;}tree[maxn*6];
seg operator + (const seg &aaa,const seg &bbb){return (seg){min(aaa.lef,bbb.lef),max(aaa.rig,bbb.rig)};}
void build(int id,int l,int r){
	maxx=max(maxx,id);
	tree[id].lef=l;tree[id].rig=r;
	if(l==r)return;
	int mid=l+r>>1;
	build(id<<1,l,mid);
	build(id<<1|1,mid+1,r);
	return;
}
void pushup(int rt){
	if(rt*2<=maxx)tree[rt].lef=min(tree[rt].lef,tree[rt<<1].lef),tree[rt].rig=max(tree[rt].rig,tree[rt<<1].rig);
	if(rt*2+1<=maxx)tree[rt].lef=min(tree[rt].lef,tree[rt<<1|1].lef),tree[rt].rig=max(tree[rt].rig,tree[rt<<1|1].rig);
	return;
}
void modify(int id,int l,int r,int place,int upl,int upr){
	if(l==r&&l==place){
		tree[id].lef=min(tree[id].lef,upl);
		tree[id].rig=max(tree[id].rig,upr);
		return;
	}
	int mid=l+r>>1;
	if(place<=mid)modify(id<<1,l,mid,place,upl,upr);
	else modify(id<<1|1,mid+1,r,place,upl,upr);
	pushup(id);return;
}
seg query(int id,int l,int r,int tol,int tor){
	if(r<tol||l>tor)return (seg){500000,0};
	if(tol<=l&&r<=tor)return tree[id];
	int mid=l+r>>1;
	return query(id<<1,l,mid,tol,tor)+query(id<<1|1,mid+1,r,tol,tor);
}
int p[maxn];
void AC(){
	random_shuffle(p+1,p+1+n);
	return;
}
signed main(){
	cin>>n;for(int i=1;i<=n;++i)cin>>x[i]>>ran[i],l[i]=r[i]=p[i]=i;
	build(1,1,n);
	for(int totot=1;totot<=7;++totot){
//		AC();
		for(int i=n;i>=1;--i){
			int res=i;i=p[i];
			int L=i,R=n,mid,idr=i,idl=i;
			while(L<=R){
				mid=L+R>>1;
				if(x[mid]<=x[i]+ran[i])idr=mid,L=mid+1;
				else R=mid-1;
			}
			L=1;R=i;
			while(L<=R){
				mid=L+R>>1;
				if(x[mid]>=x[i]-ran[i])idl=mid,R=mid-1;
				else L=mid+1;
			}
			seg point=query(1,1,n,idl,idr);
			l[i]=point.lef;r[i]=point.rig;
			modify(1,1,n,i,l[i],r[i]);
			i=res;
		}
	}
	for(int i=1;i<=n;++i)
		(ans+=i*(r[i]-l[i]+1))%=(1000000007);
	cout<<ans;
	return 0;
}