给定一个大小为n的数组,请按升序排列该数组的前k个元素,并按降序排列其余nk个元素。
例子:
Input: arr[] = {5, 4, 6, 2, 1, 3, 8, 9, -1}, k = 4
Output: 2 4 5 6 9 8 3 1 -1
Input: arr[] = {5, 4, 6}, k = 2
Output: 4 5 6
算法:
- 将前k个元素存储在数组中,并按升序对其进行排序。
- 将剩余的nk个元素存储在一个数组中,并按降序对其进行排序。
- 通过以相反的顺序添加第二个数组中的元素来合并两个数组。
C++
// C++ program to sort first k elements
// in increasing order and remaining
// n-k elements in decreasing
#include
using namespace std;
// Function to sort the array
void printOrder(int arr[], int n, int k)
{
int len1 = k, len2 = n - k;
int arr1[k], arr2[n - k];
// Store the k elements in an array
for (int i = 0; i < k; i++)
arr1[i] = arr[i];
// Store the remaining n-k elements in an array
for (int i = k; i < n; i++)
arr2[i - k] = arr[i];
// sorting the array from 0 to k-1 places
sort(arr1, arr1 + len1);
// sorting the array from k to n places
sort(arr2, arr2 + len2);
// storing the values in the final array arr
for (int i = 0; i < n; i++) {
if (i < k)
arr[i] = arr1[i];
else {
arr[i] = arr2[len2 - 1];
len2--;
}
}
// printing the array
for (int i = 0; i < n; i++)
cout << arr[i] << " ";
}
// Driver code
int main()
{
int arr[] = { 5, 4, 6, 2, 1, 3, 8, 9, -1 };
int k = 4;
int n = sizeof(arr) / sizeof(arr[0]);
printOrder(arr, n, k);
return 0;
}
Java
// Java program to sort first k elements
// in increasing order and remaining
// n-k elements in decreasing
import java.util.*;
class GFG {
// function to print half of the array in
// ascending order and the other half in
// descending order
static void printOrder(int[] arr, int n, int k)
{
int len1 = k, len2 = n - k;
int[] arr1 = new int[k];
int[] arr2 = new int[n - k];
// Store the k elements in an array
for (int i = 0; i < k; i++)
arr1[i] = arr[i];
// Store the remaining n-k elements in an array
for (int i = k; i < n; i++)
arr2[i - k] = arr[i];
// sorting the array from 0 to k-1 places
Arrays.sort(arr1, 0, k);
// sorting the array from k to n places
Arrays.sort(arr2, k, n - k);
// storing the values in the final array arr
for (int i = 0; i < n; i++) {
if (i < k)
arr[i] = arr1[i];
else {
arr[i] = arr2[len2 - 1];
len2--;
}
}
// printing the array
for (int i = 0; i < n; i++) {
System.out.print(arr[i] + " ");
}
}
// Driver code
public static void main(String[] args)
{
int arr[] = { 5, 4, 6, 2, 1, 3, 8, 9, -1 };
int k = 4;
int n = arr.length;
printOrder(arr, n, k);
}
}
Python 3
# Python 3 program to sort first
# k elements in increasing order
# and remaining n-k elements in
# decreasing
# Function to sort the array
def printOrder(arr, n, k):
len1 = k
len2 = n - k
arr1 = [0] * k
arr2 = [0] * (n - k)
# Store the k elements
# in an array
for i in range(k):
arr1[i] = arr[i]
# Store the remaining n-k
# elements in an array
for i in range(k, n):
arr2[i - k] = arr[i]
# sorting the array from
# 0 to k-1 places
arr1.sort()
# sorting the array from
# k to n places
arr2.sort()
# storing the values in the
# final array arr
for i in range(n):
if (i < k):
arr[i] = arr1[i]
else :
arr[i] = arr2[len2 - 1]
len2 -= 1
# printing the array
for i in range(n):
print(arr[i], end = " ")
# Driver code
if __name__ == "__main__":
arr = [ 5, 4, 6, 2, 1,
3, 8, 9, -1 ]
k = 4
n = len(arr)
printOrder(arr, n, k)
# This code is contributed
# by ChitraNayal
C#
// C# program to sort first k elements
// in increasing order and remaining
// n-k elements in decreasing
using System;
class GFG {
// function to print half of the array in
// ascending order and the other half in
// descending order
static void printOrder(int[] arr,
int n, int k)
{
int len2 = n - k;
int[] arr1 = new int[k];
int[] arr2 = new int[n - k];
// Store the k elements in an array
for (int i = 0; i < k; i++)
arr1[i] = arr[i];
// Store the remaining n-k
// elements in an array
for (int i = k; i < n; i++)
arr2[i - k] = arr[i];
// sorting the array from
// 0 to k-1 places
Array.Sort(arr1, 0, k);
// sorting the array from k to n places
Array.Sort(arr2, 0, n - k);
// storing the values in
// the final array arr
for (int i = 0; i < n; i++) {
if (i < k)
arr[i] = arr1[i];
else {
arr[i] = arr2[len2 - 1];
len2--;
}
}
// printing the array
for (int i = 0; i < n; i++) {
Console.Write(arr[i] + " ");
}
}
// Driver code
public static void Main()
{
int[] arr = { 5, 4, 6, 2, 1,
3, 8, 9, -1 };
int k = 4;
int n = arr.Length;
printOrder(arr, n, k);
}
}
// This code is contributed by Subhadeep
PHP
C++
// C++ program to sort first k elements
// in increasing order and remaining
// n-k elements in decreasing
#include
using namespace std;
// function to sort the array
void printOrder(int arr[], int n, int k)
{
// Sort first k elements in ascending order
sort(arr, arr + k);
// Sort remaining n-k elements in descending order
sort(arr + k, arr + n, greater());
}
// Driver code
int main()
{
int arr[] = { 5, 4, 6, 2, 1, 3, 8, 9, -1 };
int k = 4;
int n = sizeof(arr) / sizeof(arr[0]);
printOrder(arr, n, k);
for (int i = 0; i < n; i++)
cout << arr[i] << " ";
return 0;
}
Java
// Java program to sort first k elements
// in increasing order and remaining
// n-k elements in decreasing
import java.util.*;
public class SortExample {
static void printOrder(Integer[] arr, int k)
{
int n = arr.length;
// Sort first k elements in ascending order
Arrays.sort(arr, 0, k);
// Sort remaining n-k elements in descending order
Arrays.sort(arr, k, n, Collections.reverseOrder());
}
public static void main(String[] args)
{
// Our arr contains 8 elements
Integer[] arr = { 5, 4, 6, 2, 1, 3, 8, 9, -1 };
int k = 4;
printOrder(arr, k);
System.out.printf("%s", Arrays.toString(arr));
}
}
Python3
# Python3 program to sort first k elements
# in increasing order and remaining
# n-k elements in decreasing
# function to sort the array
def printOrder(arr, n, k):
# Sort first k elements in ascending order
a = arr[0:k];
a.sort();
# Sort remaining n-k elements in descending order
b = arr[k:n];
b.sort();
b.reverse();
return a + b;
# Driver code
arr = [ 5, 4, 6, 2, 1, 3, 8, 9, -1 ];
k = 4;
n = len(arr);
arr = printOrder(arr, n, k);
for i in range(n):
print(arr[i], end =" ");
# This code is contributed by mits
C#
// C# program to sort first k elements
// in increasing order and remaining
// n-k elements in decreasing
using System;
public class SortExample {
static void printOrder(int[] arr, int k)
{
int n = arr.Length;
// Sort first k elements in ascending order
Array.Sort(arr, 0, k);
// Sort remaining n-k elements in descending order
Array.Sort(arr, k, n - k);
Array.Reverse(arr, k, n - k);
}
// Driver code
public static void Main(String[] args)
{
// Our arr contains 8 elements
int[] arr = { 5, 4, 6, 2, 1, 3, 8, 9, -1 };
int k = 4;
printOrder(arr, k);
Console.Write("{0}", String.Join(" ", arr));
}
}
// This code contributed by Rajput-Ji
PHP
输出:
2 4 5 6 9 8 3 1 -1
时间复杂度: O(N * log(N))
辅助空间: O(N)
高效的方法:这个想法很简单,使用库函数按升序对前k个元素进行排序,对剩余的nk个元素进行降序排序。
C++
// C++ program to sort first k elements
// in increasing order and remaining
// n-k elements in decreasing
#include
using namespace std;
// function to sort the array
void printOrder(int arr[], int n, int k)
{
// Sort first k elements in ascending order
sort(arr, arr + k);
// Sort remaining n-k elements in descending order
sort(arr + k, arr + n, greater());
}
// Driver code
int main()
{
int arr[] = { 5, 4, 6, 2, 1, 3, 8, 9, -1 };
int k = 4;
int n = sizeof(arr) / sizeof(arr[0]);
printOrder(arr, n, k);
for (int i = 0; i < n; i++)
cout << arr[i] << " ";
return 0;
}
Java
// Java program to sort first k elements
// in increasing order and remaining
// n-k elements in decreasing
import java.util.*;
public class SortExample {
static void printOrder(Integer[] arr, int k)
{
int n = arr.length;
// Sort first k elements in ascending order
Arrays.sort(arr, 0, k);
// Sort remaining n-k elements in descending order
Arrays.sort(arr, k, n, Collections.reverseOrder());
}
public static void main(String[] args)
{
// Our arr contains 8 elements
Integer[] arr = { 5, 4, 6, 2, 1, 3, 8, 9, -1 };
int k = 4;
printOrder(arr, k);
System.out.printf("%s", Arrays.toString(arr));
}
}
Python3
# Python3 program to sort first k elements
# in increasing order and remaining
# n-k elements in decreasing
# function to sort the array
def printOrder(arr, n, k):
# Sort first k elements in ascending order
a = arr[0:k];
a.sort();
# Sort remaining n-k elements in descending order
b = arr[k:n];
b.sort();
b.reverse();
return a + b;
# Driver code
arr = [ 5, 4, 6, 2, 1, 3, 8, 9, -1 ];
k = 4;
n = len(arr);
arr = printOrder(arr, n, k);
for i in range(n):
print(arr[i], end =" ");
# This code is contributed by mits
C#
// C# program to sort first k elements
// in increasing order and remaining
// n-k elements in decreasing
using System;
public class SortExample {
static void printOrder(int[] arr, int k)
{
int n = arr.Length;
// Sort first k elements in ascending order
Array.Sort(arr, 0, k);
// Sort remaining n-k elements in descending order
Array.Sort(arr, k, n - k);
Array.Reverse(arr, k, n - k);
}
// Driver code
public static void Main(String[] args)
{
// Our arr contains 8 elements
int[] arr = { 5, 4, 6, 2, 1, 3, 8, 9, -1 };
int k = 4;
printOrder(arr, k);
Console.Write("{0}", String.Join(" ", arr));
}
}
// This code contributed by Rajput-Ji
的PHP
输出:
2 4 5 6 9 8 3 1 -1
时间复杂度: O(N * log(N))
辅助空间: O(1)