Simple way to obtain largest Number in an array or slice in golang

Toluwase Thomas — Thu, 13 Jun 2024 00:09:08 +0000

🚀 Step-by-Step Guide to Find the Largest Number in an Array in Go

Finding the largest number in an array is a common task in programming. Let's walk through a simple yet effective approach to accomplish this in Go.

📝 Steps to Follow

1️⃣ Loop through Each Value

Iterate through each element of the array or slice.

2️⃣ Declare the Initial Largest Value

Initialize a variable largest with the first element of the array:
largest := array[0]

3️⃣ Compare the Current Largest Value with Other Numbers

Compare the current largest value with each element in the array.

4️⃣ Update the Largest Value

Whenever you find a number greater than the current largest value, update largest to this new number.

5️⃣ Return the Largest Value

After completing the loop, return the largest number.

func findLargestNumber(nums []int) int {
    if len(nums) == 0 {
        return 0 // handle empty slice case
    }
    largest := nums[0] // Step 2
    for i := 1; i < len(nums); i++ { // Step 1
        if nums[i] > largest { // Step 3
            largest = nums[i] // Step 4
        }
    }
    return largest // Step 5
}

Testing the function

func TestFindLargestNumber(t *testing.T) {
    tests := []struct {
        name     string
        numbers  []int
        expected int
    }{
        {
            name:     "Mixed positive numbers",
            numbers:  []int{45, 22, 68, 90, 12},
            expected: 90,
        },
        {
            name:     "All negative numbers",
            numbers:  []int{-5, -23, -1, -55},
            expected: -1,
        },
        {
            name:     "All zeros",
            numbers:  []int{0, 0, 0, 0, 0},
            expected: 0,
        },
    }

    for _, tt := range tests {
        t.Run(tt.name, func(t *testing.T) {
            got := findLargestNumber(tt.numbers)
            if got != tt.expected {
                t.Errorf("findLargestNumber(%v) = %v, want %v", tt.numbers, got, tt.expected)
            }
        })
    }
}

Main Function

func main() {
    arr := []int{45, 22, 68, 90, 12}
    fmt.Println(findLargestNumber(arr)) // Output: 90
}

Thanks for reading.
Kindly like and share other methods you know of in the comments below.

simple ways to sum an array of numbers in golang

Toluwase Thomas — Wed, 12 Jun 2024 01:23:53 +0000

Step 1: Loop through the Array
Loop through each element of the array to access its values.

Step 2: Declare the result Variable
Declare a variable result to store the cumulative sum. The type of this variable should match the type of the elements in the array (e.g., int, float64, etc.).

Step 3: Accumulate the Sum
Use the result variable to cumulatively sum each value in the array. For example: result += array[i].

Step 4: Return the Result
After the loop completes, return the result variable which now contains the sum of all elements in the array.

func sumArray(numbers []int) int {
    result := 0
    for i := 0; i < len(numbers); i++ {
        result += numbers[i]
    }
    return result
}

Testing our function

func TestSumArray(t *testing.T) {
    tests := []struct {
        name     string
        numbers  []int
        expected int
    }{
        {
            name:     "Positive numbers",
            numbers:  []int{1, 2, 3, 4, 5},
            expected: 15,
        },
        {
            name:     "Mixed numbers",
            numbers:  []int{-3, 4, -1, 0, 2},
            expected: 2,
        },
        {
            name:     "Single number",
            numbers:  []int{10},
            expected: 10,
        },
    }

    for _, tt := range tests {
        t.Run(tt.name, func(t *testing.T) {
            got := sumArray(tt.numbers)
            if got != tt.expected {
                t.Errorf("sumArray(%v) = %v, want %v", tt.numbers, got, tt.expected)
            }
        })
    }
}

Run your test with go test ./... command via your terminal or use the play button via your IDE

Thanks for reading. Please Like and leave a comment,

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