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（一）计算数组中奇偶数和并排序

class Tool {
    int[] arr = {8, 54, 3, 47, 148, 77, 56, 55, 20};
    public void countSum(int[] array) {
        int oddSum = 0;
        int evenSum = 0;
        for (int num : array) {
            if (num % 2 == 0) {
                evenSum += num;
            } else {
                oddSum += num;
            }
        }
        System.out.println("奇数和为：" + oddSum + "\n" + "偶数和为：" + evenSum);
    }
    public void sort(int[] array) {
        // 实现冒泡排序，从大到小排序
        for (int i = 0; i < array.length - 1; i++) {
            for (int j = 0; j < array.length - 1 - i; j++) {
                if (array[j] > array[j+1]) {
                    int temp = array[j];
                    array[j] = array[j+1];
                    array[j+1] = temp;
                }
            }
        }
        System.out.println("排序后的数组为：" + Arrays.toString(array));
    }
}
public class Main {
    public static void main(String[] args) {
        int[] arr = {8, 54, 3, 47, 148, 77, 56, 55, 20};
        Tool tool = new Tool();
        tool.countSum(arr);
        tool.sort(arr);
    }
}

（二）接口与圆柱体计算

interface Computer {
    int compute(int num1, int num2);
}
class Add implements Computer {
    @Override
    public int compute(int num1, int num2) {
        return num1 + num2;
    }
}
class Subtract implements Computer {
    @Override
    public int compute(int num1, int num2) {
        return num1 - num2;
    }
}
class Multiply implements Computer {
    @Override
    public int compute(int num1, int num2) {
        return num1 * num2;
    }
}
class Divide implements Computer {
    @Override
    public int compute(int num1, int num2) {
        if (num2 == 0) {
            System.out.println("除数不能为零");
            return 0;
        }
        return num1 / num2;
    }
}
class Calculator {
    public void performCalculations(Computer operation, int a, int b) {
        operation.compute(a, b);
    }
}
public class Main {
    public static void main(String[] args) {
        Calculator calc = new Calculator();
        calc.performCalculations(new Add(), 10, 5);
        calc.performCalculations(new Subtract(), 20, 10);
        calc.performCalculations(new Multiply(), 3, 4);
        calc.performCalculations(new Divide(), 8, 2);
    }
}

（三）工具类设计

class Tool {
    int[] numbers = {8, 54, 3, 47, 148, 77, 56, 55, 20};
    void countSum() {
        int evenSum = 0;
        int oddSum = 0;
        for (int num : numbers) {
            if (num % 2 == 0) {
                evenSum += num;
            } else {
                oddSum += num;
            }
        }
        System.out.println("偶数和为：" + evenSum + "\n奇数和为：" + oddSum);
    }
    void sortArray() {
        for (int i = 0; i < numbers.length - 1; i++) {
            for (int j = 0; j < numbers.length - 1 - i; j++) {
                if (numbers[j] > numbers[j + 1]) {
                    int temp = numbers[j];
                    numbers[j] = numbers[j + 1];
                    numbers[j + 1] = temp;
                }
            }
        }
        System.out.println("排序后的数组：" + Arrays.toString(numbers));
    }
}
public class Main {
    public static void main(String[] args) {
        Tool tool = new Tool();
        tool.countSum();
        tool.sortArray();
    }
}

（四）冒泡排序实现

class SortingTool {
    int[] array = {3, 6, 2, 8, 1};
    void sort() {
        for (int i = 0; i < array.length - 1; i++) {
            for (int j = 0; j < array.length - 1 - i; j++) {
                if (array[j] > array[j + 1]) {
                    int temp = array[j];
                    array[j] = array[j + 1];
                    array[j + 1] = temp;
                }
            }
        }
        System.out.println("排序后的数组：" + Arrays.toString(array));
    }
}
public class Main {
    public static void main(String[] args) {
        SortingTool tool = new SortingTool();
        tool.sort();
    }
}

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