问答题

本题利用递归方法求前n个自然数的和(n=10)。
public class java1
public static void main(String[]args)
int sum=add(10);
System.out.println("1+2+...+9+10="+sum);
public static int add(______)
if(n==1)
______;
else
______;

【参考答案】

第1处：int n
第2处：return 1
第3处：return n+add(n-1)
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