1795 Problem A Fibonacci

问题 A: Fibonacci

时间限制: 1 Sec  内存限制: 32 MB
提交: 303  解决: 97
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题目描述

The Fibonacci Numbers{0,1,1,2,3,5,8,13,21,34,55...} are defined by the recurrence: 
F0=0 F1=1 Fn=Fn-1+Fn-2,n>=2 
Write a program to calculate the Fibonacci Numbers.

输入

Each case contains a number n and you are expected to calculate Fn.(0<=n<=30) 。

输出

For each case, print a number Fn on a separate line,which means the nth Fibonacci Number.

样例输入

1

样例输出

1

#include<iostream>
using namespace std;
int dp[50];

int F(int n) {
	if (n == 0 || n == 1) return dp[n];
	if (dp[n] != 0) return dp[n];
	else return dp[n] = F(n - 1) + F(n - 2);
}

int main() {
	int n;
	dp[0] = 0, dp[1] = 1;
	while (cin >> n) {
		cout << F(n) << endl;;
	}
	return 0;
}