#include <stdio.h>  
#include <algorithm>  
#include <assert.h>
#include <bitset>
#include <cmath>  
#include <complex>  
#include <deque>  
#include <functional>  
#include <iostream>  
#include <limits.h>  
#include <map>  
#include <math.h>  
#include <queue>  
#include <deque>
#include <set>  
#include <stdlib.h>  
#include <string.h>  
#include <string>  
#include <time.h>  
#include <unordered_map>  
#include <unordered_set>  
#include <vector>  
#include <chrono>
#include <random>
#include <time.h>
#include <fstream>
#define ll long long
#define rep2(i,a,b) for(ll i=a;i<=b;++i)
#define rep(i,n) for(ll i=0;i<n;i++)
#define rep3(i,a,b) for(ll i=a;i>=b;i--)
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pq priority_queue<int>
#define pqg priority_queue<int,vector<int>,greater<int>>
#define pb push_back
#define vec vector<int>
#define vecll vector<ll>
#define vecpii vector<pii>
#define endl "\n"
#define all(c) begin(c),end(c)
using namespace std;
int in() {int x;scanf("%d",&x);return x;}
ll lin() {ll x;scanf("%lld",&x);return x;}
void print(vec v){for(auto e:v)cout<<e<<" ";cout<<endl;}
void print(vecll v){for(auto e:v)cout<<e<<" ";cout<<endl;}
void print(map<int,int> mp){for(auto e:mp)cout<<e.first<<" "<<e.second<<endl;cout<<endl;}


const ll MOD=1e9+7;
const int N=600000;

template <ll Modulus> class modint {
  using u64 = ll;

public:
  u64 a;

  constexpr modint(const u64 x = 0) noexcept : a(((x % Modulus) + Modulus)%Modulus) {}
  constexpr u64 &value() noexcept { return a; }
  constexpr const u64 &value() const noexcept { return a; }
  constexpr modint operator+(const modint rhs) const noexcept {
    return modint(*this) += rhs;
  }
  constexpr modint operator-(const modint rhs) const noexcept {
    return modint(*this) -= rhs;
  }
  constexpr modint operator*(const modint rhs) const noexcept {
    return modint(*this) *= rhs;
  }
  constexpr modint operator/(const modint rhs) const noexcept {
    return modint(*this) /= rhs;
  }
  constexpr modint &operator+=(const modint rhs) noexcept {
    a += rhs.a;
    if (a >= Modulus) {
      a -= Modulus;
    }
    return *this;
  }
  constexpr modint &operator-=(const modint rhs) noexcept {
    if (a < rhs.a) {
      a += Modulus;
    }
    a -= rhs.a;
    return *this;
  }
  constexpr modint &operator*=(const modint rhs) noexcept {
    a = a * rhs.a % Modulus;
    return *this;
  }
  constexpr modint &operator/=(modint rhs) noexcept {
    u64 exp = Modulus - 2;
    while (exp) {
      if (exp % 2) {
        *this *= rhs;
      }
      rhs *= rhs;
      exp /= 2;
    }
    return *this;
  }
};

#define mint modint<MOD>
mint inv[N],comb[N],prd[N],invprd[N];
void calc_inv(){
    inv[1]=1;
    rep2(i,2,N-1){
        inv[i]=inv[MOD%i]*(-MOD/i);
    }
    return;
}
void calc_product(){
    prd[0]=prd[1]=1;
    invprd[0]=invprd[1]=1;
    rep2(i,2,N-1){
        prd[i]=prd[i-1]*i;
        invprd[i]=inv[i]*invprd[i-1];
    }
    return ;
}
mint cmb(int a,int b){
    if(a<b)return 0;
    if(a<0||b<0)return 0;
    return {prd[a]*invprd[b]*invprd[a-b]};
}
mint modpow(mint x,ll n){
    if(n==0) return 1;
    mint res=modpow(x*x,n/2);
    if(n&1) res=res*x;
    return res;
}
void calc(){calc_inv();calc_product();}
template<typename T>
struct BIT{
    vector<T> data;

    BIT(int size){
        data.assign(++size,0);
    }
    T sum(int k){
        T ret=0;
        for(++k;k>0;k-=k&-k) ret+=data[k];
        return (ret);
    }
    void add(int k,T x){
        for(++k;k<data.size();k+=k&-k)data[k]+=x;
    }
};
/*
和の方
BIT(size) :長さsizeで初期化
sum(k) 区間[0,k]の和を返す
add(k,x) 要素kにxを加える
*/
main(){
    calc();
    int n; cin>>n;
    BIT<mint> bit(n+1);
    vec a;
    mint m=0;
    vec zeros;
    vec vis(n+1);
    rep(i,n){
        a.pb(in());
        if(a.back()==0) m+=1;
        vis[a.back()]++;
    }
    rep2(i,1,n)if(vis[i]==0){
        zeros.pb((int)i);
    }
    sort(all(zeros));
    reverse(all(a));
    mint cnt;
    mint ans;
    mint zero;
    rep(i,n){
        if(a[i]==0){
            ans+=prd[i]*prd[m.a]*(zero)*inv[2];
            ans+=cnt*prd[m.a-1]*prd[i];
            zero+=1;
        }
        else{
            int y=a[i];
            mint num=lower_bound(all(zeros),y)-zeros.begin();
            ans+=zero*num*prd[m.a-1]*prd[i];
            ans+=bit.sum(y)*prd[m.a]*prd[i];
            bit.add(y,1);
            cnt+=(m-num);
        }
        // cout<<ans.a<<endl;
    }
    ans+=prd[m.a];
    cout<<ans.a;
}

Measured memory_bytes: 27888