Submission #545915

#	Time	Username	Problem	Language	Result	Execution time	Memory
545915		rainboy	Sure Bet (CEOI17_sure)	C11	100 / 100	101 ms	3568 KiB

sure

#include <stdio.h>

#define N	100000

double min(double a, double b) { return a < b ? a : b; }
double max(double a, double b) { return a > b ? a : b; }

unsigned int X = 12345;

int rand_() {
	return (X *= 3) >> 1;
}

void sort(double *aa, int l, int r) {
	while (l < r) {
		int i = l, j = l, k = r;
		double a = aa[l + rand_() % (r - l)], tmp;

		while (j < k)
			if (aa[j] == a)
				j++;
			else if (aa[j] > a) {
				tmp = aa[i], aa[i] = aa[j], aa[j] = tmp;
				i++, j++;
			} else {
				k--;
				tmp = aa[j], aa[j] = aa[k], aa[k] = tmp;
			}
		sort(aa, l, i);
		l = k;
	}
}

int main() {
	static double aa[N], bb[N];
	int n, i, j;
	double sum1, sum2, ans;

	scanf("%d", &n);
	for (i = 0; i < n; i++)
		scanf("%lf%lf", &aa[i], &bb[i]);
	sort(aa, 0, n);
	sort(bb, 0, n);
	sum1 = sum2 = 0, ans = 0, i = 0, j = 0;
	while (i < n || j < n) {
		if (i < n && (j == n || sum1 <= sum2))
			sum1 += aa[i++];
		else
			sum2 += bb[j++];
		ans = max(ans, min(sum1, sum2) - i - j);
	}
	printf("%.4f\n", ans);
	return 0;
}

Compilation message (stderr)

sure.c: In function 'main':
sure.c:39:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   39 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
sure.c:41:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   41 |   scanf("%lf%lf", &aa[i], &bb[i]);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 40 / 40
• Subtask 3: 40 / 40