rustLogic errorMedium

Array Indexing Error in Iterator Sum Calculation

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What it should do

Calculate the sum of elements in an array using an iterator. Example: f([1, 2, 3]) -> 6

What happens instead

thread 'main' panicked at 'attempt to subtract with overflow', src/main.rs:8:13

fn sum_array_elements(arr: &[usize]) -> usize {
    let mut sum = 0;
    for i in 0..arr.len() {
        sum += arr[i];
    }
    sum
}

fn main() {
    let arr = [1, 2, 3];
    println!("Sum: {}", sum_array_elements(&arr));
}

Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).

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This bug belongs to the logic errors pattern

The wrong operator, an inverted condition, a formula the right way round but backwards.

Learn the logic errors pattern Step through your own code

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fn sum_array_elements(arr: &[usize]) -> usize { let mut sum = 0; for i in 0..arr.len() { sum += arr[i]; } sum } fn main() { let arr = [1, 2, 3]; println!("Sum: {}", sum_array_elements(&arr)); }

Array Indexing Error in Iterator Sum Calculation

What it should do

What happens instead

More logic errors to practise

Array Indexing Error in Iterator Sum Calculation

What it should do

What happens instead

More logic errors to practise