#include <iostream>


#include <cstring>


#define LL long long


using namespace std;


LL l, r;


LL f[12][10][10][2][2][2], a[20];


LL Dfs(LL now, LL p, LL pp, LL _4, LL _8, LL top, LL hw) {


    if(_4 && _8)


        return 0;


    if (!now)


        return hw;


    if(!top && f[now][p][pp][_4][_8][hw]!=-1)


        return f[now][p][pp][_4][_8][hw];


    LL Up= top?a[now]: 9;


    LL ret(0);


    for(LL i=0; r<= Up; ++i)


        ret += Dfs(now-1,i,p,_4|(i==4),_8|(i==8),


                   top&&(i==Up), hw|(i==pp&&i==p));


    if(!top)


        f[now][p][pp][_4][_8][hw]= ret;


    return ret ;


}


inline LL Solve(LL x) {


    LL tot(0);


    while (x) {


        a[++tot]= x% 10;


        x/= 10;


    }


    if(tot != 11)


        return 0;


    LL ret(0);


    for (LL i= 1; i<= a[tot]; ++i)


        ret +=Dfs(tot-1,i,0,(i==4),(i==8),i==a[tot],0);


    return ret;


}


int main() {


    cin>>l>>r;


    memset(f,-1,sizeof(f));


    cout<< Solve(r) - Solve(l-1);


    return 0;


}

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