个人写的分割正整数方法

 import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class TestSplitInt {

	public static void main(String[] args) {
		Scanner	in=new Scanner(System.in);
		int n;
		
		while((n=in.nextInt())!=-1){
			System.out.println("你选择的是分割:"+n);
			List<String> resultList = split(n);
			
			for (String string : resultList) {
				System.out.println(string);
			}
			System.out.println("答案个数:" + resultList.size());
		}
		in.close();
		
	}

	public static List<String> split(int a) {
		List<String> result = new ArrayList<String>();
		for (int i = a; i > 0; i--) {
			int b = a - i;
			if (b == 0)
				result.add(i + "");
			else if (b <= i)
				result.add(i + "+" + b);
			if (b > 1) {
				List<String> temp = split(b);
				for (int j = 1; j < temp.size(); j++) {
					String s = temp.get(j);
					int m = Integer.parseInt(s.substring(0, s.indexOf("+")));
					if (m <= i)
						result.add(i + "+" + s);
				}
			}
		}
		return result;
	}

}

运行结果示例: