HDU2070

关于递归与使用数组记忆化

　Fibbonacci Number
Your objective for this question is to develop a program which will generate a fibbonacci number. The fibbonacci function is defined as such:

f(0) = 0
f(1) = 1
f(n) = f(n-1) + f(n-2)

Your program should be able to handle values of n in the range 0 to 50.

Input
Each test case consists of one integer n in a single line where 0≤n≤50. The input is terminated by -1.
Output
Print out the answer in a single line for each test case.
you can use 64bit integer: __int64　重要提示！！
＃＃题解
仔细读题　Ｎ的范围确定！！
常规调用函数肯定超时，重复计算的太多了，所以把题目要求范围内的结果算出来就行了
简单点　直接上代码

    #include<cstdio>
#include<iostream>
using namespace std;
int main()
{   __int64 a[52];
int i,j,n;
a[0]=0;
a[1]=1;
for( i=2;i<52;i++)
  a[i]=a[i-1]+a[i-2];
 while(scanf("%d",&n)!=EOF&&n!=-1)
 {
     printf("%I64d\n",a[n]);
 }
  return 0;


}