DSA_cpp/recursion/lec5_countNoOfHops.cpp at main · Jashans254/DSA_cpp · GitHub

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//https://www.geeksforgeeks.org/problems/count-number-of-hops-1587115620/1?utm_source=geeksforgeeks&utm_medium=ml_article_practice_tab&utm_campaign=article_practice_tab

// time limit exceeded due to recursion
//{ Driver Code Starts
#include <bits/stdc++.h>
using namespace std;

// } Driver Code Ends

class Solution
{
    public:
    //Function to count the number of ways in which frog can reach the top.
    long long countWays(int n)
    {

        // your code here
        if(n<=1)
        {
            return 1;
        }
        if(n== 2) return 2;
        if(n == 3) return 4;

        return countWays(n - 1) + countWays(n-2) + countWays(n-3);
    }
};


//{ Driver Code Starts.
int main()
{
    //taking testcases
	int t;
	cin >> t;

	while(t--)
	{
	    //taking number of steps in stair
		int n;
		cin>>n;
		Solution ob;
		//calling function countWays()
		cout << ob.countWays(n) << endl;
	}

    return 0;

}

// } Driver Code Ends