Rust Sum primes

VonRickroll
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The goal today is to write a function that returns the sum of all prime numbers up to a limit. We will do this in two steps: first we're going to write an isPrime function that checks wether or not a number is prime, and then the actual sumPrimes function.

Check if a number is prime

Write an isPrime function that takes an i32 number as parameter and returns true if this number is prime, false if it isn't.

Reminder: A prime number:

  • Can only be divided by 1 and itself
  • Is greater than 1
Write the isPrime function
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pub fn is_prime(number: i32) -> bool {
println!("The number is {}", number);
return true;
// For demo purposes:
/*
for i in 2..(number / 2 + 1) {
if number % i == 0 {
return false;
}
}
return number > 1;
*/
}
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Sum all primes

Write a sumPrimes function to sum all prime numbers up to the parameter limit included. Copy you isPrime function from the last assignment to make use of it

Write the sumPrimes function
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pub fn is_prime(number: i32) -> bool {
println!("The number is {}", number);
return true;
// For demo purposes:
/*
for i in 2..(number / 2 + 1) {
if number % i == 0 {
return false;
}
}
return number > 1;
*/
}
pub fn sum_prime(limit: i32) -> i32 {
println!("The limit is {}", limit);
return 0;
// For demo purposes:
/*
let mut sum = 0;
for x in 2..(limit+1) {
if is_prime(x) {
sum += x;
}
}
return sum;
*/
}
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