linear_search.dart

/// Write a function called linearSearch which accepts an array and a value,
/// and returns the index at which the value exists. If the value does not exist in the array, return -1.
///
/// Don't use indexOf to implement this function!
///
/// linearSearch([10, 15, 20, 25, 30], 15) // 1
/// linearSearch([9, 8, 7, 6, 5, 4, 3, 2, 1, 0], 4) // 5
/// linearSearch([100], 100) // 0
/// linearSearch([1,2,3,4,5], 6) // -1
/// linearSearch([9, 8, 7, 6, 5, 4, 3, 2, 1, 0], 10) // -1
/// linearSearch([100], 200) // -1
///
/// Time Complexity: Best O(1) - Worst O(n) - Average O(n)
/// Auxiliary Space: O(1)

void main() {
  print(linearSearch([9, 8, 7, 6, 5, 4, 3, 2, 1, 0], 4));
}

// Input: an array and a value
// Output: the index at which the value exists, or -1 if not found
int linearSearch<T>(List<T> arr, dynamic val) {
  for (int i = 0; i < arr.length; i++) {
    if (arr[i] == val) return i;
  }
  return -1;
}