Submission #304025

#	Time	Username	Problem	Language	Result	Execution time	Memory
304025		shrek12357	Watching (JOI13_watching)	C++14	0 / 100	1086 ms	384 KiB

watching

#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <map>
#include <set>
#include <climits>
#include <cmath>
#include <fstream>
#include <queue>
using namespace std;

const int MAXV = 1e9;
const int MAXN = 2005;
int n, a, b;
vector<int> nums;

int idx(int val) {
	int ans = INT_MAX;
	int lo = 0, hi = n - 1;
	while (lo <= hi) {
		int mid = (lo + hi) / 2;
		if (nums[mid] > val) {
			hi = mid - 1;
			ans = min(ans, mid);
		}
		else {
			lo = mid + 1;
		}
	}
	return ans;
}

bool check(int mid) {
	int val = 2 * mid - 1;
	int calc1[MAXN], calc2[MAXN];
	for (int i = 0; i < n; i++) {
		calc2[i] = idx(nums[i] + val);
		calc1[i] = idx(nums[i] + mid - 1);
	}
	int cur = 0;
	int c1 = 0, c2 = 0;
	while (cur < n) {
		if (calc1[cur] == calc2[cur]) {
			c1++;
			cur = calc1[cur];
		}
		else {
			c2++;
			cur = calc2[cur];
		}
	}
	if ((c1 > a && c2 >= b)||(c1 == a && c2 > b)) {
		return false;
	}
	if (c1 <= a && c2 <= b) {
		return true;
	}
	else {
		int diff1 = c1 - a, diff2 = c2 - b;
		if(diff2 > 0) {
			if (diff1 + 2 * diff2 <= 0) {
				return true;
			}
			else {
				return false;
			}
		}
	}
	return false;
}

int main() {
	cin >> n >> a >> b;
	for (int i = 0; i < n; i++) {
		int temp;
		cin >> temp;
		nums.push_back(temp);
	}
	sort(nums.begin(), nums.end());
	
	int lo = 0;
	int hi = MAXV;
	int ans = INT_MAX;
	while (lo <= hi) {
		int mid = (lo + hi) / 2;
		if (check(mid)) {
			ans = min(ans, mid);
			hi = mid - 1;
		}
		else {
			lo = mid + 1;
		}
	}
	cout << ans << endl;
}

• Subtask 1: 0 / 50
• Subtask 2: 0 / 50