Submission #784015

#	Time	Username	Problem	Language	Result	Execution time	Memory
784015		rainboy	Snail (NOI18_snail)	C11	100 / 100	2 ms	596 KiB

snail

#include <stdio.h>

#define N	10000
#define INF	0x3f3f3f3f3f3f3f3fLL

long long min(long long a, long long b) { return a < b ? a : b; }

int main() {
	static long long xx[N + 1], pp[N + 1], qq[N + 1];
	int n, i, i_;
	long long x_, x, k, k_;

	scanf("%lld%d", &x_, &n);
	for (i = 1; i <= n; i++) {
		scanf("%lld", &xx[i]);
		xx[i] += xx[i - 1];
	}
	for (i = 0; i <= n; i++)
		pp[i] = min(i == 0 ? INF : pp[i - 1], xx[i]);
	for (i = n; i >= 0; i--)
		qq[i] = min(i == n ? INF : qq[i + 1], xx[i]);
	k_ = INF, i_ = -1;
	for (i = 1; i <= n; i++) {
		x = xx[i] - pp[i];
		if (x >= x_) {
			k = 0;
			if (k_ > k || k_ == k && i_ > i)
				k_ = k, i_ = i;
		} else if (xx[n] > 0) {
			k = (x_ - x + xx[n] - 1) / xx[n];
			if (k_ > k || k_ == k && i_ > i)
				k_ = k, i_ = i;
		}
		x = xx[i] - qq[i] + xx[n];
		if (x >= x_) {
			k = 1;
			if (k_ > k || k_ == k && i_ > i)
				k_ = k, i_ = i;
		} else if (xx[n] > 0) {
			k = (x_ - x + xx[n] - 1) / xx[n] + 1;
			if (k_ > k || k_ == k && i_ > i)
				k_ = k, i_ = i;
		}
	}
	if (k_ == INF)
		printf("-1 -1\n");
	else
		printf("%lld %d\n", k_, i_ - 1);
	return 0;
}

Compilation message (stderr)

snail.c: In function 'main':
snail.c:27:26: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   27 |    if (k_ > k || k_ == k && i_ > i)
      |                  ~~~~~~~~^~~~~~~~~
snail.c:31:26: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   31 |    if (k_ > k || k_ == k && i_ > i)
      |                  ~~~~~~~~^~~~~~~~~
snail.c:37:26: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   37 |    if (k_ > k || k_ == k && i_ > i)
      |                  ~~~~~~~~^~~~~~~~~
snail.c:41:26: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   41 |    if (k_ > k || k_ == k && i_ > i)
      |                  ~~~~~~~~^~~~~~~~~
snail.c:13:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |  scanf("%lld%d", &x_, &n);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~
snail.c:15:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |   scanf("%lld", &xx[i]);
      |   ^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 9 / 9
• Subtask 3: 25 / 25
• Subtask 4: 17 / 17
• Subtask 5: 38 / 38