Submission #110712

#	Time	Username	Problem	Language	Result	Execution time	Memory
110712		ckodser	Palindrome-Free Numbers (BOI13_numbers)	C++14	72.50 / 100	3 ms	408 KiB

numbers

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 19;
ll dp[N], dp2[N], dp3[N];
ll Get(ll r)
{
	if (r < 0) return (0);
	if (r <= 9) return (r + 1);
	ll m = r, len = 0;
	int A[N];
	while (m)
		A[len ++] = m % 10, m /= 10;
	reverse(A, A + len);
	ll res = dp[len - 1];

	for (int i = 0; i < len; i++)
	{
		for (int j = 0; j < A[i]; j++)
		{
			if (i > 0 && j == A[i - 1])
				continue;
			if (i > 1 && j == A[i - 2])
				continue;
			if (i == 0)
				res += dp2[len - 1];
			else
				res += dp3[len - i - 1];
		}
		if (i > 0 && A[i] == A[i - 1])
			return (res);
		if (i > 1 && A[i] == A[i - 2])
			return (res);
	}
	if (A[len - 1] != A[len - 2] && (len == 2 || (A[len - 1] != A[len - 3])))
		res ++;
	return (res);
}
int main()
{
	dp[1] = 10;
	for (int i = 2; i < N; i++)
		dp[i] = dp[i - 1] * 8 + 11;

	dp2[0] = 1;
	dp2[1] = 9;
	for (int i = 2; i < N; i++)
		dp2[i] = dp2[i - 1] * 8;

	dp3[0] = 1;
	dp3[1] = 8;
	for (int i = 2; i < N; i++)
		dp3[i] = dp3[i - 1] * 8;

	ll l, r;
	scanf("%lld%lld", &l, &r);
	return !printf("%lld\n", Get(r) - Get(l - 1));
}

Compilation message (stderr)

numbers.cpp: In function 'int main()':
numbers.cpp:56:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld%lld", &l, &r);
  ~~~~~^~~~~~~~~~~~~~~~~~~~

• Subtask 1: 12.5 / 25
• Subtask 2: 60 / 75