Submission #303027

#	Time	Username	Problem	Language	Result	Execution time	Memory
303027		ly20	Sure Bet (CEOI17_sure)	C++17	100 / 100	268 ms	4756 KiB

sure

#include <bits/stdc++.h>
using namespace std;
const int MAXN = 112345;
vector <double> v1, v2; 
double s[MAXN];
bool cmp(double a, double b) {
	return a > b;
}
int main() {
	int n;
	scanf("%d", &n);
	for(int i = 0; i < n; i++) {
		double a, b;
		cin >> a >> b;
		v1.push_back(a); v2.push_back(b);
	}
	sort(v1.begin(), v1.end(), cmp); sort(v2.begin(), v2.end(), cmp);
	s[0] = v2[0];
	for(int i = 1; i < n; i++) {
		s[i] = s[i - 1] + v2[i];
	}
	double resp = 0;
	double sum = 0;
	for(int i = 0; i < n; i++) {
		sum += v1[i];
		int ini = 0, fim = n - 1;
		while(ini < fim) {
			int m = (ini + fim) / 2;
			if(ini == fim - 1) m = fim;
			double val1 = sum - m - 1 - i - 1, val2 = s[m] - m - 1 - i - 1;
			if(val1 < val2) {
				fim = m - 1;
			}
			else ini = m;
		}
		//printf("%d %d\n", i + 1, ini + 1);
		double val1 = sum - ini - 1 - i - 1, val2 = s[ini] - ini - 1 - i - 1;
		//printf("%lf %lf\n", val1, val2);
		resp = max(resp, min(val1, val2));
		val1 = val1 - 1; val2 = val2 - s[ini] + s[ini + 1] - 1;
		resp = max(resp, min(val1, val2));
	}
	printf("%.4lf\n", resp);
	return 0;
}

Compilation message (stderr)

sure.cpp: In function 'int main()':
sure.cpp:11:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   11 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~

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