Submission #991332

#	Time	Username	Problem	Language	Result	Execution time	Memory
991332		BF001	Mobile (BOI12_mobile)	C++17	100 / 100	337 ms	16264 KiB

mobile

#include <bits/stdc++.h>
using namespace std;
 
#define N 1000005
#define ld double
 
int n, len;
long long x[N], y[N];
 
signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    
    cin >> n >> len;
    for (int i = 1; i <= n; i++) cin >> x[i] >> y[i];
 
    ld l = 0, r = 2e9;
    while (r - l > 1e-3){
    	ld mid = (l + r) / 2.0;
    	ld cur = 0;
    	for (int i = 1; i <= n; i++){
    		ld denta = sqrt(mid * mid - y[i] * y[i]);
    		ld a = x[i] - denta;
    		ld b = x[i] + denta;
    		if (a <= cur) cur = max(cur, b);
    	}
    	if (cur >= len) r = mid;
    	else l = mid;
    }
 
    cout << fixed << setprecision(6) << l;
    
    return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 4 / 4
• Subtask 3: 4 / 4
• Subtask 4: 4 / 4
• Subtask 5: 4 / 4
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 5 / 5
• Subtask 9: 5 / 5
• Subtask 10: 5 / 5
• Subtask 11: 5 / 5
• Subtask 12: 5 / 5
• Subtask 13: 5 / 5
• Subtask 14: 5 / 5
• Subtask 15: 5 / 5
• Subtask 16: 5 / 5
• Subtask 17: 5 / 5
• Subtask 18: 5 / 5
• Subtask 19: 5 / 5
• Subtask 20: 5 / 5
• Subtask 21: 5 / 5