斐波那契数列正向实现,空间换时间,速度提升

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public class T1 {     public static void main(String[] args) {         System.out.println("hello");         System.out.println(fbnq(3L));         System.out.println(fbnq(4L));         System.out.println(fbnq(5L));         System.out.println(fbnq(6L));         System.out.println(fbnq(7L));         System.out.println(fbnq(8L));         System.out.println(fbnq(9L));         System.out.println(fbnq(10L));         System.out.println(fbnq(5000L));     }       public static long fbnq(long n) {         HashMap<Long , Long> map = new HashMap<>();         map.put(1L, 1L);         map.put(2L, 1L);         for (Long i = 3L; i <= n; i++) {             long temp =  map.get(i-1) + map.get(i-2);             map.put(i, temp);         }         return map.get(n);     } }