Data-Structures-and-Algorithms/Jacobsthal and Jacobsthal-Lucas numbers/code_1.cpp at master · shoaibrayeen/Data-Structures-and-Algorithms · GitHub

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//
//  code_1.cpp
//  Algorithm
//
//  Created by Mohd Shoaib Rayeen on 13/11/18.
//  Copyright © 2018 Shoaib Rayeen. All rights reserved.
//

#include <bits/stdc++.h>
using namespace std;

int Jacobsthal(int n) {
    if (n == 0) {
        return 0;
    }
    if (n == 1) {
        return 1;
    }
    return Jacobsthal(n - 1) + 2 * Jacobsthal(n - 2);
}

int Jacobsthal_Lucas(int n) {
    if (n == 0) {
        return 2;
    }
    if (n == 1) {
        return 1;
    }
    return Jacobsthal_Lucas(n - 1) + 2 * Jacobsthal_Lucas(n - 2);
}

int main() {
    int n;
    cout << "\nEnter n\t:\t";
    cin >> n;
    cout << "\nJacobsthal number\t:\t" << Jacobsthal(n) << endl;
    cout << "\nJacobsthal-Lucas number\t:\t" << Jacobsthal_Lucas(n) << endl;
    return 0;
}