Finding min in array java

How to Find the Minimum Value of an Array in Java: Tips and Examples

Learn how to find the minimum value of an array in Java using loops, library functions, and the Stream API. Read this article for helpful tips and examples.

• Finding the minimum value of an array using loops
• Finding the minimum value of an array using library functions
• Find The Minimum Number In A Java Array
• Sorting an array before finding the minimum value
• Finding the minimum value of an ArrayList
• Using recursion to find the minimum value of an array
• Additional code samples for finding minimum value of an array in Java
• Conclusion
• How to find the minimum of an array in Java?
• How do you find the minimum of an array?
• How to get the minimum and maximum value of an array in Java?
• How to find minimum value in array in Java 8?

Java is a popular programming language used for a wide range of applications, including web development, mobile app development, and game development. Arrays are one of the fundamental data structures in Java, and finding the minimum value of an array is a common task in many programming projects. In this blog post, we will explore several approaches for finding the minimum value of an array in Java, including using loops, library functions, and the Stream API.

Finding the minimum value of an array using loops

One approach is to initialize a variable with the first element of the array, and then loop through the array to compare each element with the current minimum and update the variable as needed. This approach is simple and straightforward, and it is suitable for small to medium-sized arrays.

int[] arr = ; int min = arr[0]; for (int i = 1; i < arr.length; i++) < if (arr[i] < min) < min = arr[i]; >> System.out.println("The minimum value of the array is: " + min); 

In the code example above, we first create an array called arr with five elements. We then initialize a variable called min with the first element of the array. We then loop through the array and compare each element with the current minimum value. If the current element is smaller than the current minimum value, we update the min variable to the current element.

When the loop finishes, we have the minimum value of the array stored in the min variable. We then print out the result using the System.out.println() method.

When using this approach, it is important to initialize the variable with a value in the array, check the length of the array before accessing elements, and avoid unnecessary memory allocation.

Finding the minimum value of an array using library functions

Another approach is to use the library functions min_element() and max_element() to find the minimum and maximum values of the array. This approach is more concise and elegant than using loops, and it is suitable for small to medium-sized arrays.

int[] arr = ; int min = Arrays.stream(arr).min().getAsInt(); System.out.println("The minimum value of the array is: " + min); 

In the code example above, we first create an array called arr with five elements. We then use the Arrays.stream() method to convert the array into a stream. We then use the min() method to find the minimum value of the stream. Finally, we use the getAsInt() method to extract the minimum value as an integer.

When using this approach, it is important to remember that the Arrays class provides useful methods for working with arrays in Java.

Find The Minimum Number In A Java Array

Finding the smallest value in a Java array.This tutorial will show and explain how to find the Duration: 3:32

Sorting an array before finding the minimum value

To find the smallest number in an array, we can sort the array first and return the first element. This approach is useful when we need to find the minimum value of a large array, or when we need to find the minimum value multiple times.

int[] arr = ; Arrays.sort(arr); int min = arr[0]; System.out.println("The minimum value of the array is: " + min); 

In the code example above, we first create an array called arr with five elements. We then use the Arrays.sort() method to sort the array in ascending order. Finally, we extract the minimum value as the first element of the sorted array.

When using this approach, it is important to remember that sorting an array can be expensive in terms of time and memory, and it may not be the most efficient approach for all scenarios.

Finding the minimum value of an ArrayList

The Collections.min() method can be used to find the minimum value of an ArrayList in Java. This approach is similar to using library functions to find the minimum value of an array.

ArrayList arrList = new ArrayList(); arrList.add(5); arrList.add(3); arrList.add(8); arrList.add(2); arrList.add(7); int min = Collections.min(arrList); System.out.println("The minimum value of the ArrayList is: " + min); 

In the code example above, we first create an ArrayList called arrList with five elements. We then use the Collections.min() method to find the minimum value of the ArrayList . Finally, we extract the minimum value as an integer.

When using this approach, it is important to remember that the Collections class provides useful methods for working with collections in Java.

Using recursion to find the minimum value of an array

Recursion can also be used to find the minimum value of an array. This approach is elegant and concise, but it may not be the most efficient approach for large arrays.

public static int findMin(int[] arr, int n) < if (n == 1) < return arr[0]; >return Math.min(arr[n-1], findMin(arr, n-1)); > int[] arr = ; int min = findMin(arr, arr.length); System.out.println("The minimum value of the array is: " + min); 

In the code example above, we first define a recursive function called findMin() that takes an array and its length as input. If the length of the array is 1, we return the first element of the array. Otherwise, we recursively call the findMin() function with the array and its length minus 1, and return the minimum value of the last element of the array and the result of the recursive call.

When using this approach, it is important to remember that recursion may not be the most efficient approach for large arrays.

Additional code samples for finding minimum value of an array in Java

In Java , for example, min of an array java code example

public int min() < int min = elementData[0]; for (int i = 1; i < size; i++) < if (elementData[i] < min) < min = elementData[i]; >> return min; >

In Java , find minimum number in array java code example

public class MinimumNumber< public static void main(String[] args)< int[] arr=new int[]; int min=arr[0]; for(int i=0;i > System.out.println("Minimum Number in array:"+min); > >

In Java , for example, find min in array java code example

private static int findMin(int[] array) < int min = array[0]; for(int i=1;iarray[i]) < min = array[i]; >> return min; >

In Java , in particular, get minimum of array java code example

int /*OR*/ double /*OR*/ float[] array_of_numbers = /*For this example we're just using a regular integer array*/ int min = array_of_numbers[0]; /*Important to initialise the first value. */ for (int i = 0; i < array_of_numbers.length; i++) < if(array_of_numbers[i] < min) < /* So now we can make the comparison*/ min = array_of_numbers[i]; /* If smaller, make it the new minimum*/ >> System.out.println("Minimum value in array: " + min)

In Java , in particular, find minimum in array java code example

 public static void main(String[] args) < int[] xr = ; //find maximum value int max = xr[0]; for (int i = 0; i < xr.length; i++) < if (xr[i] >max) < max = xr[i]; >> //find minimum value int min=xr[0]; for (int i = 0; i > System.out.println("max: "+max); System.out.println("min: "+min); >

Conclusion

There are several ways to find the minimum value of an array in Java, including using loops, library functions, and the Stream API. Sorting the array and using recursion are also viable options, but may not be the most efficient for all scenarios. By understanding the different approaches, developers can choose the best method for their specific project needs. The key takeaway from this article is that there is no one-size-fits-all solution for finding the minimum value of an array in Java, and the best approach depends on the specific requirements of the project.

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Find Max and Min in an Array in Java

Learn to find the smallest and the largest item in an array in Java. We will discuss different approaches from simple iterations to the Stream APIs.

In the given examples, we are taking an array of int values. We can apply all the given solutions to an array of objects or custom classes as well. In the case of custom objects, we only need to override the equals() method and provide the correct logic to compare two instances.

int[] items = < 10, 0, 30, 2, 7, 5, 90, 76, 100, 45, 55 >; // Min = 0, Max = 100

1. Find Max/Min using Stream API

Java streams provide a lot of useful classes and methods for performing aggregate operations. Let’s discuss a few of them.

The Stream interface provides two methods max() and min() that return the largest and the smallest item from the underlying stream.

Both methods can take a custom Comparator instance if we want a custom comparison logic between the items.

For primitives, we have IntStream , LongStream and DoubleStream to support sequential and parallel aggregate operations on the stream items. We can use the java.util.Arrays.stream() method to convert the array to Stream and then perform any kind of operation on it.

int max = Arrays.stream(items) .max() .getAsInt(); // 100 int min = Arrays.stream(items) .min() .getAsInt(); // 0

In the above example, we find the array’s max and min items in two separate steps. We are creating the stream two times and operating on it two times. This is useful when we only have to find either the maximum item or the minimum item.

If we have to find the max and min item both then getting the max and min item from the array in a single iteration makes complete sense. We can do it using the IntSummaryStatistics instance. A similar instance is available for LongStream and DoubleStream as well.

IntSummaryStatistics stats = Arrays.stream(items).summaryStatistics(); stats.getMax(); //100 stats.getMin(); //0

2. Collections.min() and Collections.max()

The Collections class provides the aggregate operations for items in a collection such as List. We can convert an array into a List and use these APIs to find the max and min items.

In the given example, we are converting the int[] to Integer[]. If you have an Object[] already then you can directly pass the array to Arrays.asList() API.

Integer min = Collections.min(Arrays.asList(ArrayUtils.toObject(items))); Integer max = Collections.max(Arrays.asList(ArrayUtils.toObject(items)));

Sorting the array is also a good approach for small arrays. For large arrays, sorting may prove a performance issue so choose wisely.

In a sorted array, the min and max items will be at the start and the end of the array.

Arrays.sort(items); max = items[items.length - 1]; //100 min = items[0]; //0

This is the most basic version of the solution. The pseudo-code is :

Initialize the max and min with first item in the array Iterate the array from second position (index 1) Compare the ith item with max and min if current item is greater than max set max = current item elseif current item is lower than min set min = current item

After the loop finishes, the max and min variable will be referencing the largest and the smallest item in the array.

max = items[0]; min = items[0]; for (int i = 1; i < items.length; i++) < if (items[i] >max) < max = items[i]; >else if (items[i] < min) < min = items[i]; >> System.out.println(max); //100 System.out.println(min); //0

Recursion gives better performance for a big-size unsorted array. Note that we are writing the recursive call for max and min items, separately. If we need to find both items in a single invocation, we will need to change the program as per demand.

This solution is basically Divide and Conquer algorithm where we only handle the current index and the result of the rest (the recursive call) and merge them together for the final output.

For getting the maximum of items, at each item, we return the larger of the current items in comparison and all of the items with a greater index. A similar approach is for finding the minimum item.

min = getMax(items, 0, items[0]); //0 min = getMin(items, 0, items[0]); //100 public static int getMax(final int[] numbers, final int a, final int n) < return a >= numbers.length ? n : Math.max(n, getMax(numbers, a + 1, numbers[a] > n ? numbers[a] : n)); > private static int getMin(final int[] numbers, final int a, final int n)

In this short Java tutorial, we learned the different ways to find the maximum and the minimum element from an Array in Java. We learned to use the Stream API, Collections API, simple iterations, and advanced techniques such as recursion.

For smaller arrays, we should prefer the code readability and use the Stream or Collection APIs. For large arrays, where we will get noticeable performance improvements, using recursion can be considered.

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