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How to calculate the sum of all prime numbers between two given numbers in Kotlin

How to calculate the sum of all prime numbers between two given numbers in Kotlin.

Here's a step-by-step tutorial on how to calculate the sum of all prime numbers between two given numbers in Kotlin:

Step 1: Define a function to check if a number is prime​

To calculate the sum of prime numbers, we first need to determine if a number is prime or not. We can do this by creating a function that checks whether a given number is divisible by any number less than itself. If it is divisible by any number other than 1 and itself, then it is not a prime number.

fun isPrime(number: Int): Boolean {
    if (number <= 1) {
        return false
    }
    for (i in 2 until number) {
        if (number % i == 0) {
            return false
        }
    }
    return true
}

Step 2: Get the range of numbers to consider​

Next, we need to get the range of numbers between which we want to find the prime numbers. Let's say we have two numbers start and end representing the range.

val start = 1
val end = 100

Step 3: Calculate the sum of prime numbers​

Now that we have the range of numbers, we can iterate through each number within the range and check if it is prime. If it is prime, we add it to a running total sum.

var sum = 0
for (number in start..end) {
    if (isPrime(number)) {
        sum += number
    }
}

Step 4: Print the sum of prime numbers​

Finally, we can print the sum of all the prime numbers within the given range.

println("The sum of prime numbers between $start and $end is: $sum")

Step 5: Putting it all together​

Here's the complete code:

fun isPrime(number: Int): Boolean {
    if (number <= 1) {
        return false
    }
    for (i in 2 until number) {
        if (number % i == 0) {
            return false
        }
    }
    return true
}

fun main() {
    val start = 1
    val end = 100

    var sum = 0
    for (number in start..end) {
        if (isPrime(number)) {
            sum += number
        }
    }

    println("The sum of prime numbers between $start and $end is: $sum")
}

That's it! You now have a program that calculates the sum of all prime numbers between two given numbers in Kotlin.