我试图通过按降序对树集进行排序来找到数组的第三大元素,但是某些测试用例对某些输入值失败,而大多数测试用例对某些输入值通过。
我的代码:
// { Driver Code Starts
import java.util.Scanner;
import java.util.*;
import java.io.*;
class ThirdLargestElement
{
public static void main(String args[])
{
Scanner sc = new Scanner(System.in);
int t = sc.nextInt();
while(t>0)
{
long n =sc.nextLong();
Long arr[] = new Long[(int)n];
for(long i=0;i<n;i++)
arr[(int)i] = sc.nextLong();
GfG g = new GfG();
System.out.println(g.thirdLargest(arr));
t--;
}
}
}// } Driver Code Ends
class GfG
{
long thirdLargest(Long a[])
{
// Your code here
if(a.length<3)
return -1;
else{
TreeSet<Long> ts=new TreeSet<Long>(new myComparator());
for(long i:a)
ts.add(i);
ArrayList<Long> al=new ArrayList<Long>(ts);
return al.get(2);
}
}
}
class myComparator implements Comparator{
public int compare(Object obj1,Object obj2){
Long a=(Long) obj1;
Long b=(Long) obj2;
if(a<b)
return 1;
else if(a>b)
return -1;
else
return 0;
}
}
Link to the question where you can run the code
请更正此代码。
TreeSet
并使用流获得第三大数字,while(t>0)
{
long n =sc.nextLong();
TreeSet<Long> ts=new TreeSet<>(Comparator.comparingLong(Long::longValue).reversed());
for(long i=0;i<n;i++)
ts.add(sc.nextLong());
long thirdLast = ts.stream()
.limit(3)
.skip(2)
.mapToLong(e->e)
.findAny().orElse(0l);
System.out.println(thirdLast);
t--;
}
尝试此一个
class GfG {
long thirdLargest(Long a[]) {
Arrays.sort(a);
List<Long> numbers = Arrays.asList(a);
Collections.reverse(numbers);
return numbers.size() >= 3 ? numbers.get(2) : -1;
}
}