#include <bits/stdc++.h>
#define lp(i,a,b) for(int i=a;i<b;i++)
#define ll long long
#define pii pair<int,int>
#define ff first
#define ss second
const int maxn=5e5+10 ;
const int MOD=1e9+7 ;
using namespace std ;
struct node
{
double a , la ;
ll b , lb1 , lb2 ;
node()
{
a = la = 0 ;
b = lb1 = lb2 = 1 ;
}
} ;
node tree[4*maxn] ;
int m(int l, int r){ return (l+r)/2 ; }
void refresh(int pos, int l, int r)
{
double k1 = tree[pos].la ;
ll k2 = tree[pos].lb1 ;
ll k3 = tree[pos].lb2 ;
tree[pos].la = 0 ;
tree[pos].lb1 = 1 ;
tree[pos].lb2 = 1 ;
tree[pos].b = (tree[pos].b/k3) ;
tree[pos].b = (tree[pos].b*k2) % MOD ;
tree[pos].a += k1 ;
if(l==r) return ;
lp(i,0,2)
{
tree[pos*2+i].la += k1 ;
tree[pos*2+i].lb1 = (tree[pos*2+i].lb1*k2) % MOD ;
tree[pos*2+i].lb2 = (tree[pos*2+i].lb2*k3) % MOD ;
}
}
void merge(int pos)
{
tree[pos].a = max(tree[pos*2].a, tree[pos*2+1].a) ;
tree[pos].b = (tree[pos*2].a > tree[pos*2+1].a) ? tree[pos*2].b : tree[pos*2+1].b ;
}
void pointUpd(int pos, int l, int r ,int x, double v, ll b1 , ll b2)
{
refresh(pos,l,r) ;
if(l>x or r < x) return ;
if(l==r)
{
tree[pos].a += v ;
tree[pos].b = (tree[pos].b*b1)%MOD ;
tree[pos].b = (tree[pos].b/b2) % MOD ;
return ;
}
pointUpd(pos*2,l,m(l,r),x,v,b1,b2) ;
pointUpd(pos*2+1,m(l,r)+1,r,x,v,b1,b2) ;
merge(pos) ;
}
void intervalUpd(int pos, int l, int r , int beg, int en, double v, ll b1 ,ll b2)
{
refresh(pos, l, r) ;
if(l>en or r < beg) return ;
if(l>=beg && r<=en)
{
tree[pos].la += v ;
tree[pos].lb1 = (tree[pos].lb1*b1) % MOD ;
tree[pos].lb2 = (tree[pos].lb2*b2) % MOD ;
refresh(pos, l, r) ;
return ;
}
intervalUpd(pos*2, l,m(l,r),beg,en,v,b1,b2) ;
intervalUpd(pos*2+1,m(l,r)+1,r,beg,en,v,b1,b2) ;
merge(pos) ;
}
void print(int pos, int l, int r)
{
refresh(pos,l,r) ;
printf("%d e %d: %lld\n", l,r,tree[pos].b) ;
if(l==r) return ;
print(pos*2,l,m(l,r)) ;
print(pos*2+1,m(l,r)+1,r) ;
}
// -------- x --------
int n , x[maxn] , y[maxn] ;
ll ans()
{
refresh(1,0,n-1) ;
return tree[1].b ;
}
int updateY(int pos, int val)
{
pointUpd(1,0,n-1,pos,-log2(y[pos]),1,y[pos]) ;
pointUpd(1,0,n-1,pos,log2(val),val,1) ;
y[pos] = val ;
return ans() ;
}
int updateX(int pos, int val)
{
intervalUpd(1,0,n-1,pos,n-1,-log2(x[pos]), 1, x[pos]) ;
intervalUpd(1,0,n-1,pos,n-1,log2(val),val,1) ;
x[pos] = val ;
return ans() ;
}
int init(int N, int X[], int Y[])
{
n = N ;
lp(i,0,n) x[i] = X[i] ;
lp(i,0,n) y[i]=Y[i] ;
ll acProduct=1 ;
double logProduct = log2(1) ;
lp(i,0,n)
{
acProduct = (acProduct*x[i]) % MOD ;
logProduct += log2(x[i]) ;
pointUpd(1,0,n-1,i,log2(y[i]) + logProduct , (acProduct*y[i])%MOD,1 ) ;
}
return ans();
}
