# Minimum steps to reach the Nth stair in jumps of perfect power of 2

Given N stairs, the task is to find the minimum number of jumps of perfect power of 2 requires to reach the Nth stair.

Examples:

Input: N = 5
Output:
Explanation:
We can take jumps from 0->1->4.
So the minimum jumps require are 2.

Input: N = 23
Output: 4
Explanation:
We can take jumps from 0->1->2->4->16.
So the minimum jumps required are 4.

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach: Since the jumps are required to be in perfect power of 2. So the count of set bit in the given number N is the minimum number of jumps required to reach Nth stair as the summation of 2i for all set bit index i is equals to N.

Below is the implementation of the above approach:

## C++

 `// C++ program for the above approach ` `#include "bits/stdc++.h" ` `using` `namespace` `std; ` ` `  `// Function to count the number of jumps ` `// required to reach Nth stairs. ` `int` `stepRequired(``int` `N) ` `{ ` ` `  `    ``int` `cnt = 0; ` ` `  `    ``// Till N becomes 0 ` `    ``while` `(N) { ` ` `  `        ``// Removes the set bits from ` `        ``// the right to left ` `        ``N = N & (N - 1); ` `        ``cnt++; ` `    ``} ` ` `  `    ``return` `cnt; ` `} ` ` `  `// Driver Code ` `int` `main() ` `{ ` ` `  `    ``// Number of stairs ` `    ``int` `N = 23; ` ` `  `    ``// Function Call ` `    ``cout << stepRequired(N); ` `    ``return` `0; ` `} `

## Java

 `// Java program for the above approach ` ` `  `import` `java.util.*; ` ` `  `class` `GFG{ ` ` `  `// Function to count the number of jumps ` `// required to reach Nth stairs. ` `static` `int` `stepRequired(``int` `N) ` `{ ` ` `  `    ``int` `cnt = ``0``; ` ` `  `    ``// Till N becomes 0 ` `    ``while` `(N > ``0``) { ` ` `  `        ``// Removes the set bits from ` `        ``// the right to left ` `        ``N = N & (N - ``1``); ` `        ``cnt++; ` `    ``} ` ` `  `    ``return` `cnt; ` `} ` ` `  `// Driver Code ` `public` `static` `void` `main(String[] args) ` `{ ` ` `  `    ``// Number of stairs ` `    ``int` `N = ``23``; ` ` `  `    ``// Function Call ` `    ``System.out.print(stepRequired(N)); ` `} ` `} ` ` `  `// This code is contributed by PrinciRaj1992 `

## Python3

 `# Python3 program for the above approach ` ` `  `# Function to count the number of jumps ` `# required to reach Nth stairs. ` `def` `stepRequired(N): ` ` `  `    ``cnt ``=` `0``; ` ` `  `    ``# Till N becomes 0 ` `    ``while` `(N > ``0``): ` ` `  `        ``# Removes the set bits from ` `        ``# the right to left ` `        ``N ``=` `N & (N ``-` `1``); ` `        ``cnt ``+``=` `1``; ` `    ``return` `cnt; ` ` `  `# Driver Code ` `if` `__name__ ``=``=` `'__main__'``: ` ` `  `    ``# Number of stairs ` `    ``N ``=` `23``; ` ` `  `    ``# Function Call ` `    ``print``(stepRequired(N)); ` `     `  `# This code is contributed by 29AjayKumar `

## C#

 `// C# program for the above approach ` `using` `System; ` ` `  `class` `GFG{ ` ` `  `// Function to count the number of  ` `// jumps required to reach Nth stairs. ` `static` `int` `stepRequired(``int` `N) ` `{ ` `    ``int` `cnt = 0; ` ` `  `    ``// Till N becomes 0 ` `    ``while` `(N > 0) ` `    ``{ ` ` `  `        ``// Removes the set bits from ` `        ``// the right to left ` `        ``N = N & (N - 1); ` `        ``cnt++; ` `    ``} ` ` `  `    ``return` `cnt; ` `} ` ` `  `// Driver Code ` `public` `static` `void` `Main(String[] args) ` `{ ` ` `  `    ``// Number of stairs ` `    ``int` `N = 23; ` ` `  `    ``// Function Call ` `    ``Console.Write(stepRequired(N)); ` `} ` `} ` ` `  `// This code is contributed by 29AjayKumar `

Output:

```4
```

Time Complexity: O(log N)

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.

My Personal Notes arrow_drop_up Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.

Improved By : princiraj1992, 29AjayKumar

Article Tags :
Practice Tags :

1

Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.