Dynamic programming, fibonacci number, memoization

fib.cpp

#include <iostream>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <cstring>
#include <stack>
#include <queue>
#include <set>
#include <cassert>
#include <map>
#include <bitset>
#include <vector>
#include <climits>
#define MAX 1000
typedef long long int lli;
using namespace std;
lli a[MAX];
lli getNum(lli x){
	if(a[x]!=INT_MIN){
		return a[x];
	}
}
int output(int x){
	lli f;
	if(getNum(x)!=INT_MIN){
		f=getNum(x);
	}
	if(x<=2){
		f=1;
	}
	else{
		f=output(x-1)+output(x-2);
	}
	a[x]=f;
	return f;
}
int main(){
	fill(a, a+MAX, INT_MIN);
	lli n=3;
	//cin >> n;
	/*for(int i=0;i<n;i++){
		lli t;
		cin >> t;
		cout << output(t) << endl;
	} */
	cout << output(2) << endl;
	cout << output(3) << endl;
	cout << output(5) << endl;
	return 0;
}