Submission #3778881

---

Source Code Expand

#include <bits/stdc++.h>
using namespace std;
#define IOS ios::sync_with_stdio(false), cin.tie(0)
#define REP(i, n) for (int i = 0; i < n; i++)
#define FOR(i, a, b) for (int i = a; i < b; i++)
#define ALL(x) (x).begin(), (x).end()
#define dump(x) cout << (x) << endl
#define LMAX 9223372036854775807LL
#define LMIN -9223372036854775807LL
using ll = int64_t;
template<typename T>
using vec = vector<T>;
using P = pair<ll, ll>;
template <typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val){
	fill((T *)array, (T *)(array + N), val);
}

const ll INF = 1e16;
const ll MOD = 1e9 + 7;
//int dx[4] = {1,0,-1,0};
//int dy[4] = {0,1,0,-1};
//ll pas[5001][5002];
string s;
ll n, d;
ll dp[10003][2][102];

ll rec(ll i, bool tit, ll sum){
	ll &tmp = dp[i][tit][sum];
	if(~tmp)return tmp;
	if(i == n){
		return (sum % d == 0);
	}
	tmp = 0;
	ll MX = (tit ? s[i] - '0' : 9);
	for(int j = 0;j <= MX;j++){
		tmp += rec(i + 1,tit && j == MX,(sum + j) % d);
		tmp %= MOD;
	}
	return tmp;
}

signed main(){
	IOS;
	cin >> d >> s;
	n = s.size();
	Fill(dp, -1);
	dump(rec(0, true, 0) - 1);
}

Submission Info

Judge Result