hdu3652

基本的数位dp，需要记录前面除以13的余数。

#include <cstdio>
#include <cstring>
using namespace std;

#define D(x) x

const int MAX_DIGIT = ;

int n, m;
int f[MAX_DIGIT];
int memoize[MAX_DIGIT][][][][];

void to_digits(int a)
{
    for (int i = ; i < MAX_DIGIT; i++)
    {
        f[i] = a % ;
        a /= ;
    }
}

int dfs(int digit, bool less, bool contain, bool one, int remain)
{
    if (digit == -)
    {
        return contain && !remain;
    }
    if (memoize[digit][less][contain][one][remain] != -)
    {
        return memoize[digit][less][contain][one][remain];
    }
    int limit = less ?  : f[digit];
    int ret = ;
    for (int i = ; i <= limit; i++)
    {
        int new_remain = (remain *  + i) % ;
        if (i ==   && one)
        {
            ret += dfs(digit - , less || i < f[digit], true, false, new_remain);
            continue;
        }
        if (i == )
        {
            ret += dfs(digit - , less || i < f[digit], contain, true, new_remain);
            continue;
        }
        ret += dfs(digit - , less || i < f[digit], contain, false, new_remain);
    }
    memoize[digit][less][contain][one][remain] = ret;
    return ret;
}

int main()
{
    while (scanf("%d", &n) != EOF)
    {
        to_digits(n);
        memset(memoize, -, sizeof(memoize));
        int ans = dfs(, false, false, false, );
        printf("%d\n", ans);
    }
    return ;
}