#include <bits/stdc++.h>
#define syosu(x) fixed<<setprecision(x)
using namespace std;
typedef long long ll;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int,int> P;
typedef pair<double,double> pdd;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<string> vs;
typedef vector<P> vp;
typedef vector<vp> vvp;
typedef vector<pll> vpll;
typedef pair<int,P> pip;
typedef vector<pip> vip;
const int inf=1<<30;
const ll INF=1ll<<60;
const double pi=acos(-1);
const double eps=1e-8;
const ll mod=1e9+7;
const int dx[4]={-1,0,1,0},dy[4]={0,-1,0,1};

ll Pow(ll n,ll p){
	ll r=1;
	for(;p>0;p>>=1){
		if(p&1) r=(r*n)%mod;
		n=(n*n)%mod;
	}
	return r;
}

ll n;

int f(int x){
	int t=0;
	while(x){
		x/=10;
		t++;
	}
	return t;
}

int main(){
	cin>>n;
	ll res=0;
	for(int i=1;i<=n;i++) if(n/i>=8){
		if(n%i==0) (res+=Pow(10,n/i-1)*9-i+1+mod)%=mod;
		else res++;
	}
	res%=mod;
	ll I=1,t=0;
	for(int i=1;i<10000000;i++){
		t-=f(i-1);
		while(t<n) t+=f(I++);
		if(t==n) res++;
	}
	res%=mod;
	cout<<res<<endl;
}
### Prompt

Construct a cpp code solution to the problem outlined:

For a positive integer n, let us define f(n) as the number of digits in base 10.

You are given an integer S. Count the number of the pairs of positive integers (l, r) (l \leq r) such that f(l) + f(l + 1) + ... + f(r) = S, and find the count modulo 10^9 + 7.

Constraints

* 1 \leq S \leq 10^8

Input

Input is given from Standard Input in the following format:


S


Output

Print the answer.

Examples

Input

1


Output

9


Input

2


Output

98


Input

123


Output

460191684


Input

36018


Output

966522825


Input

1000


Output

184984484

### Response

```cpp
#include <bits/stdc++.h>
#define syosu(x) fixed<<setprecision(x)
using namespace std;
typedef long long ll;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int,int> P;
typedef pair<double,double> pdd;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<string> vs;
typedef vector<P> vp;
typedef vector<vp> vvp;
typedef vector<pll> vpll;
typedef pair<int,P> pip;
typedef vector<pip> vip;
const int inf=1<<30;
const ll INF=1ll<<60;
const double pi=acos(-1);
const double eps=1e-8;
const ll mod=1e9+7;
const int dx[4]={-1,0,1,0},dy[4]={0,-1,0,1};

ll Pow(ll n,ll p){
	ll r=1;
	for(;p>0;p>>=1){
		if(p&1) r=(r*n)%mod;
		n=(n*n)%mod;
	}
	return r;
}

ll n;

int f(int x){
	int t=0;
	while(x){
		x/=10;
		t++;
	}
	return t;
}

int main(){
	cin>>n;
	ll res=0;
	for(int i=1;i<=n;i++) if(n/i>=8){
		if(n%i==0) (res+=Pow(10,n/i-1)*9-i+1+mod)%=mod;
		else res++;
	}
	res%=mod;
	ll I=1,t=0;
	for(int i=1;i<10000000;i++){
		t-=f(i-1);
		while(t<n) t+=f(I++);
		if(t==n) res++;
	}
	res%=mod;
	cout<<res<<endl;
}
```