CF 55D Beautiful numbers 数位DP

#include<cstdio>
#include<cstring>
#include<algorithm>
#define ll __int64
using namespace std;
int bit[20],hash[2529];
ll dp[20][2521][50];
int gcd(int a,int b)
{
if(a<b) swap(a,b);
while(b){
int t=a;
a=b;
b=t%b;
}
return a;
}
ll dfs(int pos,int num,int lcm,bool f)
{
if(pos==-1) return num%lcm==0;
if(!f&&dp[pos][num][hash[lcm]]!=-1) return dp[pos][num][hash[lcm]];
ll ans=0;
int e=f?bit[pos]:9;
for(int i=0;i<=e;i++){
int g=lcm;
if(i>=2) g=g/gcd(g,i)*i;
ans+=dfs(pos-1,(num*10+i)%2520,g,f&&(i==bit[pos]));
}
if(!f) dp[pos][num][hash[lcm]]=ans;
return ans;
}
ll cal(ll n)
{
int m=0;
while(n){
bit[m++]=n%10;
n/=10;
}
return dfs(m-1,0,1,1);
}
int main()
{
ll n,m;
int t,i,j;
memset(dp,-1,sizeof(dp));
for(j=0,i=1;i<=2520;i++){
if(2520%i==0)
hash[i]=j++;
}
scanf("%d",&t);
while(t--){
scanf("%I64d%I64d",&n,&m);
printf("%I64d\n",cal(m)-cal(n-1));
}
}