Implementing the Selection Sort Algorithm in Java

Selection sort is a simple and intuitive sorting algorithm. Its core idea is to repeatedly select the smallest (or largest) element from the unsorted portion and place it at the end of the sorted portion until the entire array is sorted. The basic approach involves an outer loop to determine the end position of the sorted portion, and an inner loop to find the minimum value in the unsorted portion, followed by swapping this minimum value with the element at the current position of the outer loop. In Java implementation, the `selectionSort` method is implemented with two nested loops: the outer loop iterates through the array (with `i` ranging from 0 to `n-2`), and the inner loop (with `j` ranging from `i+1` to `n-1`) finds the index `minIndex` of the minimum value in the unsorted portion. Finally, the element at position `i` is swapped with the element at `minIndex`. Taking the array `{64, 25, 12, 22, 11}` as an example, the sorted array `[11, 12, 22, 25, 64]` is gradually constructed through each round of swaps. The time complexity is O(n²), making it suitable for small-scale data. This algorithm has a simple logic and easy-to-implement code, serving as a typical example for understanding the basic sorting concepts.