题解

#include<bits/stdc++.h>
using namespace std;
int a[10] = {6,2,5,5,4,5,6,3,7,6};
int ch(int x)
{
int sum=0;
if(x == 0) return a[x];
while(x)
{
sum += a[x % 10];
x /= 10;
}
return sum;
}
int n,cnt;
int main()
{
cin >> n;
n -= 4;
for(int i = 0;i <= 1000;i++)
{
for(int j = 0;j <= 1000;j++)
{
if(ch(i) + ch(j) + ch(i+j) == n) cnt++;
}
}
cout << cnt << endl;
return 0;
}