Submission #45297

#	Time	Username	Problem	Language	Result	Execution time	Memory
45297		bugmenot111	Sure Bet (CEOI17_sure)	C++17	100 / 100	146 ms	18492 KiB

sure

/*
maximize min(s[a] - (a + b), s[b] - (a + b))
min(s[a], s[b]) - (a + b)
min(s[a], s[b]) - b
*/
#include <cstdio>
#include <algorithm>
#include <numeric>
#include <functional>
#define MAXN 100100
double a[MAXN];
double b[MAXN];
double pa[MAXN];
double pb[MAXN];
int n;
int main(void) {
	double best = 0;
	scanf("%d", &n);
	for(int i = 0; i < n; i++) {
		scanf("%lf %lf", &a[i], &b[i]);
	}
	std::sort(a, a + n, std::greater<double>());
	std::sort(b, b + n, std::greater<double>());
	std::partial_sum(a, a + n, pa);
	std::partial_sum(b, b + n, pb);
	for(int i = 0; i < n; i++) {
		double x = pa[i];
		double y1 = 0, y2 = 0;
		auto it = std::upper_bound(pb, pb + n, x);
		if(it != pb + n) y1 = std::min(x, *it) - std::distance(pb, it) - i - 2;
		if(it != pb) it = std::prev(it);
		y2 = std::min(x, *it) - std::distance(pb, it) - i - 2;
		best = std::max(best, std::max(y1, y2));
	}
	printf("%.4lf", best);
	return 0;
}

Compilation message (stderr)

sure.cpp: In function 'int main()':
sure.cpp:18:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
  ~~~~~^~~~~~~~~~
sure.cpp:20:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lf %lf", &a[i], &b[i]);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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