Sum up an array of integers in C#

This post will discuss how to sum up an array of integers in C#.

1. Using `Enumerable.Sum` Method

Starting with .NET 3.5, you can use the Enumerable.Sum method to compute the sum of a sequence of numeric values. It is available in System.Linq namespace and can be used as follows:

using System;

using System.Linq;

public class Example

{

public static void Main()

{

int[] arr = { 5, 3, 7, -1, 2};

int sum = arr.Sum();

Console.WriteLine("Sum is " + sum);

}

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Output:

Sum is 16

The sum() method is overloaded for Decimal, Double, Int32, and Int64 values. For other numeric data types like Short and Long, do as follows:

using System;

using System.Linq;

public class Example

{

public static void Main()

{

short[] arr = { 5, 3, 7, -1, 2 };

int sum = arr.Select(x => (int)x).Sum();

Console.WriteLine("Sum is " + sum);

}

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Output:

Sum is 16

2. Using `Enumerable.Aggregate` Method

Another efficient way of accomplishing this would be with the Aggregate() method by LINQ, which applies an accumulator function over a sequence. Here’s an example of its usage:

using System;

using System.Linq;

public class Example

{

public static void Main()

{

int[] arr = { 5, 3, 7, -1, 2};

int sum = arr.Aggregate((x, y) => x + y);

Console.WriteLine("Sum is " + sum);

}

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Output:

Sum is 16

3. Using `ForEach` method

If you don’t prefer LINQ or do not use .NET 3.5 or above, you can use a foreach loop to compute the sum of an array of integers.

using System;

public class Example

{

public static void Main()

{

int[] arr = { 5, 3, 7, -1, 2 };

int sum = 0;

foreach (var i in arr) {

sum += i;

}

Console.WriteLine("Sum is " + sum);

}

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Output:

Sum is 16

Here’s an equivalent version using the Array.ForEach method.

using System;

public class Example

{

public static void Main()

{

int[] arr = { 5, 3, 7, -1, 2};

int sum = 0;

Array.ForEach(arr, delegate(int i) {

sum += i;

});

Console.WriteLine("Sum is " + sum);

}

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Output:

Sum is 16

That’s all about summing up an array of integers in C#.

Sum up an array of integers in C#

1. Using Enumerable.Sum Method

2. Using Enumerable.Aggregate Method

3. Using ForEach method

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1. Using `Enumerable.Sum` Method

2. Using `Enumerable.Aggregate` Method

3. Using `ForEach` method