用java编程求下列多项式前k项的和，1 - 1/2 + 2/3 - 3/4 +4/5 - 5/6 + ...

以下是使用Java编程求解多项式前k项的和的示例代码：

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int k = scanner.nextInt();
        double sum = 0;
        int sign = 1;
        for (int i = 1; i <= k; i++) {
            sum += sign * i / (i + 1.0);
            sign = -sign;
        }
        System.out.printf("%.4f", sum);
    }
}