Selection Sort

Introduction

1. Initialization:

   • The function selectionSort accepts an array arr as its argument.

   • The variable n stores the length of the array.

2. Outer Loop:

   • The outer loop iterates through each element in the array, treating each element as the starting point.

3. Finding the Minimum:

   • Assume the first element of the unsorted part as the minimum (minIndex = i).

   • The inner loop starts from the next element (j = i + 1) and checks each element to find the smallest one.

   • If a smaller element is found, update minIndex to the index of that element.

4. Swapping Elements:

   • After finding the minimum element in the unsorted part, swap it with the first element of the unsorted part.

   • Only perform the swap if the minimum element is different from the starting element.

5. Return the Result:

   • After all elements are processed, the sorted array arr is returned.

Code

function selectionSort(arr) {
  const length = arr.length;

  // Loop through each element in the array
  for (let curr = 0; curr < length; curr++) {
    let minIndex = curr;

    // Check the rest of the array for a smaller element
    for (let next = curr + 1; next < length; next++) {
      if (arr[next] < arr[minIndex]) {
        minIndex = next;
      }
    }

    // Swap the minimum element with current index
    if (curr != minIndex) {
      [arr[curr], arr[minIndex]] = [arr[minIndex], arr[curr]];
    }
  }

  return arr;
}

console.log(selectionSort([20, 12, 10, 15, 2]));