365算法每日学计划
39打卡:
思路:
import java.util.Arrays;
import java.util.Scanner;
public class _39 {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int m = input.nextInt();
while (m-- > 0) {
int n = input.nextInt();
double[] a = new double[n];
for (int i = 0; i < a.length; i++) {//每个喷水装置的初始化
a[i] = input.nextDouble();
}
//采用贪心算法,所以先对每个喷水装置的半径进行排序,从大的开始
Arrays.sort(a);
int num = 0;
double sum = 0;
for (int i = a.length - 1; i >= 0; i--) {
if (i > 1) {
//计算圆与长方形相交的正方形的面积
sum += Math.sqrt(a[i] * a[i] - 1) * 2;
num++;
if (sum >= 20) {
break;
}
}
}
System.out.println(num);
}
}
}