1. Selection Sort – an array sorting algorithm
Basic operation (ascending)
Divide the array into sorted and unsorted sections
Keep track of the beginning of the sorted section (i.e. it’s index value)
Initially the entire array will be unsorted
Find the maximum element in the unsorted section
Swap it into the last position (in the unsorted section)
Update the sorted/unsorted partitioning
Go back to step 2
Repeat until entire array is sorted (i.e. in the sorted section)
Descending sort is similar
Just look for minimum elements

2. spot is last element in the unsorted portion of the list
Initial Array (step 1)
int list[] = { 84, 91, 76, 69, 94, 86 };
[0]
[1]
[2]
[3]
[4]
[5] 84 91 76 69 94 86
list
items= 6
Unsorted portion of list
spot = 5
spot is last element in the unsorted portion of the list

3. Step 2 Find max element in unsorted portion list items= 6 [0] [1] [2]
[3]
[4]
[5] 84 91 76 69 94 86
list
items= 6
Unsorted portion of list
spot = 5
indMax= 4

4. Step 3 Swap max element with last element in unsorted portion list
Swap elements 86 94
list
[0]
[1]
[2]
[3]
[4]
[5] 84 91 76 69 94 86
items= 6
Unsorted portion of list
spot = 5
indMax= 4
i.e. swap item at “spot” with item at “indMax”

5. Step 4 Update sorted/unsorted portions (i.e. update spot) list
Go back to step 2
[0]
[1]
[2]
[3]
[4]
[5] 84 91 76 69 86 94
list
items= 6
Unsorted
Sorted
spot = 4

6. Step 2 – second time Find max element in unsorted portion list
[0]
[1]
[2]
[3]
[4]
[5] 84 91 76 69 86 94
list
items= 6
Unsorted
Sorted
spot = 4
indMax= 1

7. Step 3 – second time
Swap max element with last element in unsorted portion
Swap elements 86 91
list
[0]
[1]
[2]
[3]
[4]
[5] 84 91 76 69 86 94
items= 6
Unsorted
Sorted
spot = 4
indMax= 1
i.e. swap item at “spot” with item at “indMax”

8. Step 4 – second time
Update sorted/unsorted portions (i.e. update spot)
Go back to step 2
list
[0]
[1]
[2]
[3]
[4]
[5] 84 86 76 69 91 94
items= 6
Unsorted
Sorted
spot = 3

9. Done Array is sorted (stop when spot == 0) list items= 6 [0] [1] [2]
[3]
[4]
[5] 69 76 84 86 91 94
items= 6
Unsorted
Sorted
spot = 0