fn binary_search(arr: &[i32], target_value: &i32) -> Option<usize> {
let array_length = arr.len();
let mut min_index: i32 = 0;
let mut max_index: i32 = array_length as i32 - 1;
while min_index <= max_index {
let middle_index = ((max_index - min_index) / 2) + min_index;
let middle_index_as_usize = middle_index as usize;
let middle_value = &arr[middle_index_as_usize];
if middle_value == target_value {
return Some(middle_index_as_usize);
}
if middle_value < target_value {
min_index = middle_index + 1;
}
if middle_value > target_value {
max_index = middle_index - 1;
}
}
None
}
fn log_binary_search_result(arr: &[i32], target_value: &i32) -> () {
if let Some(result) = binary_search(&arr, &target_value) {
println!("Encontrado {} en el índice {} de la matriz.", target_value, result);
} else {
println!("{} no se encontró en la matriz.", target_value);
}
}
fn main() -> () {
let arr: [i32; 20] = [
1, 10, 20, 47, 59, 63, 75, 88, 99, 107, 120, 133, 155, 162, 176, 188, 199, 200, 210, 222,
];
let target: i32 = 88;
log_binary_search_result(&arr, &target)
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn assert_value_is_found() {
let valid_arr = [
1, 10, 20, 47, 59, 63, 75, 88, 99, 107, 120, 133, 155, 162, 176, 188, 199, 200, 210,
222,
];
for i in 0..valid_arr.len() {
assert_eq!(i, binary_search(&valid_arr, &valid_arr[i]).unwrap());
}
}
#[test]
fn assert_value_is_not_found() {
let sorted_arr = [
1, 10, 20, 47, 59, 63, 75, 88, 99, 107, 120, 133, 155, 162, 176, 188, 199, 200, 210,
222,
];
let unsorted_arr = [
2, 22, 48, 58, 61, 73, 84, 90, 100, 119, 132, 154, 160, 177, 187, 197, 201, 211, 2242,
];
for i in 0..unsorted_arr.len() {
assert_eq!(None, binary_search(&sorted_arr, &unsorted_arr[i]));
}
}
}
