最小化所有可能子数组的最大和最小元素之间的差异
给定一个大小为N的数组arr[ ] ,任务是找到 arr[ ] 的所有可能大小的子数组的最大和最小元素之间的最小差异。例子:
Input: arr[] = { 5, 14, 7, 10 }
Output: 3
Explanation: {7, 10} is the subarray having max element = 10 & min element = 7, and their difference = 10 – 7 = 3
Input: arr[] = { 2, 6, 15, 7, 6 }
Output: 1
Explanation: {7, 6} is the subarray having max element = 7 & min element = 6, and their difference = 7 – 6 = 1
方法:简单的想法是使用两个循环并检查每个子数组,最大和最小元素之间的最小差异。跟踪差异并返回可能的最小差异。这种方法的时间复杂度是二次的。
有效方法:这个想法是利用我们可以通过仅迭代大小为2的子数组来获得最小差异的事实。
假设我们的子数组中有两个元素。让最大和最小元素之间的差为x 。现在,如果我们在子数组的右侧或左侧包含一个元素,则最大元素或最小元素可能会被更新。随着最大或最小元素的更新,此更改最终将使我们的差异x增加。
按照以下步骤实施上述方法:
- 迭代数组并跟踪最小相邻差
- 打印这个最小差异作为结果。
下面是上述方法的实现:
C++
// C++ program for the above approach
#include
using namespace std;
// Function to get the min difference
// between max and min element of all
// possible subarrays
int getMinDifference(int arr[], int n)
{
// To store the adjacent difference
int diff;
// To compare with min difference
int mn = INT_MAX;
for (int i = 1; i < n; i++) {
// Storing adjacent difference
diff = abs(arr[i] - arr[i - 1]);
// Updating the min difference
mn = min(diff, mn);
}
// Returning min difference
return mn;
}
// Driver code
int main()
{
int arr[] = { 2, 6, 15, 7, 6 };
int N = sizeof(arr) / sizeof(arr[0]);
cout << getMinDifference(arr, N);
return 0;
}
Java
// Java program for the above approach
import java.io.*;
class GFG{
// Function to get the min difference
// between max and min element of all
// possible subarrays
static int getMinDifference(int []arr, int n)
{
// To store the adjacent difference
int diff = 0;
// To compare with min difference
int mn = Integer.MAX_VALUE;
for (int i = 1; i < n; i++) {
// Storing adjacent difference
diff = Math.abs(arr[i] - arr[i - 1]);
// Updating the min difference
mn = Math.min(diff, mn);
}
// Returning min difference
return mn;
}
// Driver code
public static void main (String[] args)
{
int []arr = {2, 6, 15, 7, 6 };
int N = arr.length;
System.out.println(getMinDifference(arr, N));
}
}
// This code is contributed by shivanisinghss2110
Python3
# Python3 program for the above approach
import sys,math
# Function to get the min difference
# between max and min element of all
# possible subarrays
def getMinDifference(arr, n) :
INT_MAX = sys.maxsize;
# To compare with min difference
mn = INT_MAX;
for i in range(1, n):
# Storing adjacent difference
diff = abs(arr[i] - arr[i - 1]);
# Updating the min difference
mn = min(diff, mn);
# Returning min difference
return mn;
# Driver code
if __name__ == "__main__" :
arr = [ 2, 6, 15, 7, 6 ];
N = len(arr);
print(getMinDifference(arr, N));
# This code is contributed by AnkThon
C#
// C# program for the above approach
using System;
using System.Collections.Generic;
class GFG{
// Function to get the min difference
// between max and min element of all
// possible subarrays
static int getMinDifference(int []arr, int n)
{
// To store the adjacent difference
int diff = 0;
// To compare with min difference
int mn = Int32.MaxValue;
for (int i = 1; i < n; i++) {
// Storing adjacent difference
diff = Math.Abs(arr[i] - arr[i - 1]);
// Updating the min difference
mn = Math.Min(diff, mn);
}
// Returning min difference
return mn;
}
// Driver code
public static void Main()
{
int []arr = {2, 6, 15, 7, 6 };
int N = arr.Length;
Console.Write(getMinDifference(arr, N));
}
}
// This code is contributed by SURENDRA_GANGWAR.
Javascript
1
时间复杂度: O(N),N是元素的数量
辅助空间: O(1)