BZOJ 4521 手机号码

SB数位dp.

我的貌似要特判9999999999的情况。

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
long long l,r,dp[][][][][][],ret=,bit[];
void reset()
{
    for (long long i=;i<=;i++)
        for (long long j=;j<=;j++)
            for (long long k=;k<=;k++)
                for (long long l=;l<=;l++)
                    for (long long a=;a<=;a++)
                        for (long long b=;b<=;b++)
                            dp[i][j][k][l][a][b]=-;
}
void get_bit(long long x)
{
    ret=;
    while (x) {bit[++ret]=x%;x/=;}
}
long long dfs(long long pos,long long cnt,long long num,long long f,long long f1,long long f2,bool flag)
{
    if (!pos) return f;
    if ((!flag) && (dp[pos][cnt][num][f][f1][f2]!=-)) return dp[pos][cnt][num][f][f1][f2];
    long long ans=,up=flag?bit[pos]:,tc;
    for (long long i=;i<=up;i++)
    {
        if ((i==) && (f2)) continue;
        if ((i==) && (f1)) continue;
        if (i==num) tc=min(cnt+,3LL);else tc=;
        ans+=dfs(pos-,tc,i,f|(tc==),f1|(i==),f2|(i==),flag&&(i==up));
    }
    if (!flag) dp[pos][cnt][num][f][f1][f2]=ans;
    return ans;
}
long long ask(long long x)
{
    get_bit(x);
    if (x==9999999999LL) return dfs(ret,,,,,,);
    else return dfs(ret,,-,,,,);
}
int main()
{
    scanf("%lld%lld",&l,&r);reset();
    printf("%lld\n",ask(r)-ask(l-));
    return ;
}