Submission #37604

#	Time	Username	Problem	Language	Result	Execution time	Memory
37604		14kg	Palindrome-Free Numbers (BOI13_numbers)	C++11	100 / 100	0 ms	1132 KiB

numbers

#include <stdio.h>

bool check[11][11][21];
long long d[11][11][21];

long long f(int x, int y, int len) {
	if (len == 0) return 1;

	if (!check[x][y][len]) {
		check[x][y][len] = true;

		if (x == 10 && y == 10) {
			for (int i = 1; i < 10; i++) d[x][y][len] += f(10, i, len - 1);
			d[x][y][len] += f(10, 10, len - 1);
		}
		else if (x == 10) {
			for (int i = 0; i < 10; i++)
				if (i != y) d[x][y][len] += f(y, i, len - 1);
		}
		else {
			for (int i = 0; i < 10; i++) {
				if (i == x || i == y) continue;
				d[x][y][len] += f(y, i, len - 1);
			}
		}
	} return d[x][y][len];
}

long long out(long long x) {
	long long sum = 0, check_m;
	int len = 0, temp[21] = { 0 }, in[21] = { 0 };
	
	while (x) temp[++len] = x % 10, x /= 10;
	for (int i = 1; i <= len; i++) in[len - i + 1] = temp[i];

	in[0] = 10;
	for (int i = len; i >= 2; i--) {
		check_m = 1;
		for (int j = 2; j < i; j++)
			if (in[j - 2] == in[j] || in[j - 1] == in[j]) check_m = 0;

		for (int j = 0; j < in[i]; j++)
			if (j != in[i - 1] && j != in[i - 2]) sum += f(in[i - 1], j, len - i)*check_m;
	}
	for (int i = 1; i < in[1]; i++) sum += f(10, i, len - 1);
	sum += f(10, 10, len - 1);

	check_m = 1;
	for (int j = 2; j <=len; j++)
		if (in[j - 2] == in[j] || in[j - 1] == in[j]) check_m = 0;

	return sum + check_m;
}

int main() {
	long long x, y, sum;

	scanf("%lld %lld", &x, &y);	

	sum = y ? out(y) : 1;
	if (x > 1) sum -= out(x - 1);
	else if (x == 1) sum -= 1;

	printf("%lld", sum);
}

Compilation message (stderr)

numbers.cpp: In function 'int main()':
numbers.cpp:58:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld %lld", &x, &y); 
                            ^

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