public class test { //裴波纳契级数 public static void main(String[] args) { int n=30; int n1 = 1; //第一个数 int n2 = 1; //第二个数 int sum = 0; //和 for(int i=3;i<n;i++){ sum = n1+n2; n1=n2; n2=sum; } System.out.println("sum:"+sum); } }