ソートの選択

ソートの選択

思考アルゴリズム

アルゴリズム実装

import random

def selection_sort(data):
    for stand in range(len(data) - 1):
        lowest = stand
        for index in range(stand + 1, len(data)):
            if data[lowest] > data[index]:
                lowest = index
        data[lowest], data[stand] = data[stand], data[lowest]
    return data
    
data_list = random.sample(range(100), 10)
selection_sort(data_list)

import java.util.Arrays;

public class SelectionSort {

    static void swap(int[] a, int i, int j) {
        int temp = a[i];
        a[i] = a[j];
        a[j] = temp;
    }

    static void selectionSort(int[] a) {
        for (int i = 0; i < a.length - 1; i++) {
        	int minIndex = i;
        	for (int j = i + 1; j < a.length; j++ ) {
        		if (a[minIndex] > a[j]) {
        			minIndex = j;
        		}
        	}
            swap(a, i, minIndex);
        }
    }

    public static void main(String[] args) {
        int[] a = { 17, 14, 11, 19, 13, 15, 18, 12, 16, 20 };

        selectionSort(a);
        System.out.println(Arrays.toString(a));
    }
}

時間分析の実行