Submission #1254567

#	Time	Username	Problem	Language	Result	Execution time	Memory
1254567		XXBabaProBerkay	Palindrome-Free Numbers (BOI13_numbers)	C++20	13.75 / 100	1 ms	328 KiB

numbers

#include <bits/stdc++.h>
using namespace std;

#define F first
#define S second
#define MP make_pair
#define PB push_back

using ll = long long;
using ld = long double;
using pi = pair<int, int>;
using pll = pair<ll, ll>;

template<typename T>
using vec = vector<T>;

template<typename T, int N>
using arr = array<T, N>;

ll gcd(ll a, ll b) { return b == 0 ? a : gcd(b, a % b); }
ll lcm(ll a, ll b) { return a * b / gcd(a, b); }

const ll INF = 1e18;
const int MOD = 998244353;

vec<int> num;
ll dp[2][10][10][20];

ll f(bool g, int d1, int d2, int i)
{
	if (i >= (int)num.size()) return 1;
	if (dp[g][d1][d2][i] != -1)
		return dp[g][d1][d2][i];

	dp[g][d1][d2][i] = 0;
	for (int j = 0; j <= (g ? 9 : num[i]); j++)
	{
		if ((i >= 2 && j == d2) || (i >= 1 && j == d1)) continue;
		dp[g][d1][d2][i] += f(g || j < num[i], j, d1, i + 1);
	}

	return dp[g][d1][d2][i];
}

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

	memset(dp, -1, sizeof dp);

	int a, b;
	cin >> a >> b;
	a--;
	while (a > 0)
	{
		num.PB(a % 10);
		a /= 10;
	}
	reverse(num.begin(), num.end());

	ll x = f(0, 0, 0, 0);

	memset(dp, -1, sizeof dp);

	num.clear();
	while (b > 0)
	{
		num.PB(b % 10);
		b /= 10;
	}
	reverse(num.begin(), num.end());

	ll y = f(0, 0, 0, 0);

	cout << y - x << '\n';
}

• Subtask 1: 8.75 / 25
• Subtask 2: 5 / 75