#include<cstdio>
#include<algorithm> 
#include<iostream>
using namespace std;
bool check(int x)    //判断是否有2，4 
{
    while(x)
    {
        if(x%10==2||x%10==4)
           return true;    
        x/=10;
    }
    return false;
}
int main()
{
    int cnt=0;
    for(int i=1;i<=2019;i++)
    {
        if(check(i)) continue;
        for(int j=i+1;j<=2019;j++)
        {
            if(check(j)) continue;
            int k=2019-i-j;
            if(k<=i||k<=j||check(k))continue;
            cnt+=1;
        }
     } 
     cout<<cnt<<endl;
     return 0;
} 

#include<cstdio>
#include<algorithm> 
#include<iostream>
using namespace std;
int main()
{
    int n,sum=0;
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        if(i%10==1||i/10==1||i%10==2||i/10==2||i%10==9||i/10==9||i%10==0)
          sum+=i;
    }
    cout<<sum<<endl;
}

#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
const int maxn = 1e5+10;
int w[maxn];
int ans[maxn];
int main(){
    int n;
    scanf("%d", &n);
    for(int i = 1; i <= n; i++){
        scanf("%d", &w[i]);
    }
    if(w[1]==w[2])   //常数列的情况 
    {
        printf("%d", n);
        return 0;
    }
    sort(w+1, w+n+1);//先排序，从小到大 
    for(int i = 1; i < n; i++){
        ans[i] = w[i+1]-w[i];     //依次算出两数之差 
    }
    int G = ans[1];
    for(int i = 2; i <= n-1; i++){
        G = gcd(G, ans[i]);
    }
    printf("%d\n", (w[n]-w[1])/G+1);
    return 0;
}