Sum with Closure in Rust

Rust Closures and Higher-Order Functions: Exercise-8 with Solution

Write a Rust function that takes a closure and a slice of integers, applies the closure to each element, and returns the sum of the results.

Sample Solution:

Rust Code:

fn sum_with_closure<F>(slice: &[i32], closure: F) -> i32
where
    F: Fn(i32) -> i32, // Closure trait bound
{
    // Use the fold method to iterate over the slice, applying the closure to each element and accumulating the sum
    slice.iter().map(|&x| closure(x)).sum()
}

fn main() {
    let numbers = [1, 2, 3, 4, 5];
    println!("Numbers: {:?}", numbers); // Print the numbers
    let sum = sum_with_closure(&numbers, |x| x * 2); // Example usage: doubling each element and summing them
    println!("Sum: {}", sum); // Print the sum
}

Output:

Numbers: [1, 2, 3, 4, 5]
Sum: 30

Explanation:

The above code defines "sum_with_closure()" takes a slice of integers (&[i32]) and a closure as arguments. The closure takes an integer and returns another integer. The function applies the closure to each element in the slice, transforms them using the closure, and sums up the results. Finally, it returns the sum.

In the "main()" function, an example usage of "sum_with_closure()" is demonstrated. It creates a slice of integers [1, 2, 3, 4, 5] and then applies a closure that doubles each number. Finally, it prints the sum of the transformed numbers.

Rust Code Editor:

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