#include <bits/stdc++.h>
#define mod 1000000007
using namespace std;
stack <pair<unsigned long long,unsigned long long>> S;
unsigned long long n,v[100005],i,dr[100005],st[100005],x,j,val,Max,nr,nr2;
unsigned long long suma[100001],total;
pair <unsigned long long,unsigned long long> sor[100005];
unsigned long long bin(unsigned long long x){
x %= mod;
return ((x*(x+1))/2)%mod;
}
unsigned long long rectCount(unsigned long long x, unsigned long long y){
return (bin(x)*bin(y))%mod;
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin>>n;
for(i=1;i<=n;i++){
cin>>v[i];
if(v[i] == v[i-1])
nr++;
if(v[i] >= v[i-1])
nr2++;
sor[i].first = v[i];
sor[i].second = i;
dr[i] = n + 1;
}
sort(sor+1,sor+n+1);
for(i=1;i<=n;i++){
cin>>x;
suma[i] = suma[i-1] + x;
}
for(i=1;i<=n;i++){
x = v[i];
while(S.empty() == false && x<S.top().first){
dr[S.top().second] = i;
S.pop();
}
S.push({x,i});
}
while(S.empty() == false){
S.pop();
}
for(i=n;i>=1;i--){
x = v[i];
while(S.empty() == false && x < S.top().first){
st[S.top().second] = i;
S.pop();
}
S.push({x,i});
}
if(nr != n - 1 && nr2 != n){
//brut
for(i=1;i<=n;i++){
total += rectCount(suma[dr[sor[i].second]-1] - suma[st[sor[i].second]],sor[i].first) % mod;
for(j=1;j<=i-1;j++){
if(st[sor[j].second] <= sor[i].second && dr[sor[j].second] >= sor[i].second)
Max = sor[j].first;
}
total -= rectCount(suma[dr[sor[i].second]-1] - suma[st[sor[i].second]],Max) % mod;
}
}
else if(nr2 == n){
//subtask 5
for(i=1;i<=n;i++){
total += rectCount(suma[dr[sor[i].second]-1] - suma[st[sor[i].second]],sor[i].first) % mod;
total -= rectCount(suma[dr[sor[i].second]-1] - suma[st[sor[i].second]],sor[i-1].first) % mod;
}
}
else{
//subtask 4
total = rectCount(suma[n],v[1]);
}
cout << total % mod;
return 0;
Compilation message
fancyfence.cpp: In function 'int main()':
fancyfence.cpp:83:13: error: expected '}' at end of input
83 | return 0;
| ^
fancyfence.cpp:20:1: note: to match this '{'
20 | {
| ^
