#include <bits/stdc++.h>
#include "horses.h"
using namespace std;
using ll = long long;
using pii = pair<ll, ll>;
const int MOD = 1e9+7;
const ll INF = 1e18;
vector<ll> x;
vector<ll> y;
int n;
vector<int> nx, pr;
struct SegTree {
vector<ll> tree;
SegTree() {
}
void init(int m) {
tree.assign(4*m, 0);
}
void query(int p, int l, int r, int i, int x) {
if (l > i || r < i) return;
if (l==r) {
tree[p] = x;
}
else {
int m = (l+r)/2;
query(2*p, l, m, i, x);
query(2*p+1, m+1, r, i, x);
ll i1 = tree[2*p];
ll i2 = tree[2*p+1];
tree[p] = (i1*i2) % MOD;
}
}
ll rsq(int p, int l, int r, int i, int j) {
if (l > j || r < i) return 1;
if (i <= l && r <= j) {
return tree[p];
}
else {
int m = (l+r)/2;
ll i1 = rsq(2*p, l, m, i, j);
ll i2 = rsq(2*p+1, m+1, r, i, j);
return (i1*i2)%MOD;
}
}
void querymx(int p, int l, int r, int i, int x) {
if (l > i || r < i) return;
if (l == r) {
tree[p] = x;
}
else {
int m = (l+r)/2;
querymx(2*p, l, m, i, x);
querymx(2*p+1, m+1, r, i, x);
int i1 = tree[2*p];
int i2 = tree[2*p+1];
tree[p] = max(i1, i2);
}
}
int rmq(int p, int l, int r, int i, int j) {
if (l > j || r < i) return 0;
if (i <= l && r <= j) {
return tree[p];
}
else {
int m = (l+r)/2;
int i1 = rmq(2*p, l, m, i, j);
int i2 = rmq(2*p+1, m+1, r, i, j);
return max(i1, i2);
}
}
};
SegTree st, mxtr;
ll compute() {
int m = x.size();
int idx=m-1;
for (int i=0; i<40; i++) {
idx = pr[idx];
}
ll prod = 1;
bool moduled=false;
for (int i = nx[idx]; i<n; i=nx[i]) {
ll y0 = mxtr.rmq(1, 0, n-1, idx, nx[idx]-1);
ll y1 = mxtr.rmq(1, 0, n-1, i, nx[i]-1);
prod *= x[i];
//cout << idx << " " << i << " " << y0 << " " << y1 << endl;
if (prod >= MOD) {
prod %= MOD;
moduled = true;
}
if (moduled) {
idx = i;
prod = 1;
moduled = false;
}
else {
if (prod*y1 >= y0) {
idx = i;
prod = 1;
moduled = false;
}
}
}
int last = y[idx];
ll y0 = mxtr.rmq(1, 0, n-1, idx, nx[idx]-1);
prod = st.rsq(1, 0, n-1, 0, idx);
return (prod*y0)%MOD;
}
int init(int N, int* a, int* b) {
n = N;
x.assign(n, 0);
y.assign(n, 0);
for (int i=0; i<n; i++) {
x[i] = a[i];
y[i] = b[i];
}
st.init(n);
mxtr.init(n);
for (int i=0; i<n; i++) {
st.query(1, 0, n-1, i, x[i]);
mxtr.querymx(1, 0, n-1, i, y[i]);
}
pr.assign(n, -1);
nx.assign(n, -1);
pr[0] = 0;
int last = 0;
nx[n-1] = n;
for (int i=1; i<n; i++) {
pr[i] = last;
if (x[i] != 1) {
last = i;
}
}
last = (x[n-1] == 1 ? n : n-1);
for (int i=n-2; i>=0; i--) {
nx[i] = last;
if (x[i] != 1) {
last = i;
}
}
return compute();
}
int updateX(int pos, int val) {
st.query(1, 0, n-1, pos, val);
if (val != 1 && x[pos] == 1 && pos != 1) {
nx[pr[pos]] = pos;
pr[nx[pos]] = pos;
}
else if (val == 1 && x[pos] != 1) {
nx[pr[pos]] = nx[pos];
pr[nx[pos]] = pr[pos];
}
x[pos] = val;
return compute();
}
int updateY(int pos, int val) {
y[pos] = val;
mxtr.querymx(1, 0, n-1, pos, val);
return compute();
}
