不要62(数位dp)

不要62

LL dfs(int pos,int prev,bool limit){
    int i;
    if(pos==0) return 1;
    if(!limit&&dp[pos][prev]!=-1) return dp[pos][prev];
    int up;
    LL ans=0;
    up = limit?a[pos]:9;
    for(i = 0;i <= up;i ++){
        if(prev==6&&i==2) continue;
        if(i==4) continue;
        ans += dfs(pos-1,i,limit&&i==up);
    }
    if(!limit) dp[pos][prev] = ans;
    return ans;
}
LL solve(int n){
    len = 0;
    while(n!=0){
        int x = n%10;
        n /= 10;
        a[++len] = x;
    }
    LL ans = dfs(len,0,1);
    return ans;
}