Wednesday, October 8, 2025
HomeData Modelling & AIMin operations to reduce N by multiplying by any number or taking...

Min operations to reduce N by multiplying by any number or taking square root

Given a number N, the task is to find the minimum value of N by applying below operations any number of times: 

Examples: 
 

Input: N = 20 
Output: 10
Explanation: 
Multiply -> 20 * 5 = 100 
sqrt(100) = 10, which is the minimum value obtainable.

Input: N = 5184 
Output:
Explanation:
sqrt(5184) = 72. 
Multiply -> 72*18 = 1296 
sqrt(1296) = 6, which is the minimum value obtainable.
 

 

Approach: This problem can be solved using Greedy Approach. Below are the steps:

  1. Keep replacing N to sqrt(N) until N is a perfect square.
  2. After the above step, iterate from sqrt(N) to 2, and for every, i keep replacing N with N / i if N is divisible by i2.
  3. The value of N after the above step will be the minimum possible value.

Below is the implementation of the above approach:

C++




// C++ program for above approach
#include <bits/stdc++.h>
using namespace std;
 
// Function to reduce N to its minimum
// possible value by the given operations
void minValue(int n)
{
    // Keep replacing n until is
    // an integer
    while (int(sqrt(n)) == sqrt(n)
        && n > 1) {
        n = sqrt(n);
    }
 
    // Keep replacing n until n
    // is divisible by i * i
    for (int i = sqrt(n);
        i > 1; i--) {
 
        while (n % (i * i) == 0)
            n /= i;
    }
 
    // Print the answer
    cout << n;
}
 
// Driver Code
int main()
{
    // Given N
    int N = 20;
 
    // Function Call
    minValue(N);
}


Java




// Java implementation of the above approach
import java.lang.Math;
 
class GFG{
 
// Function to reduce N to its minimum
// possible value by the given operations
static void minValue(int n)
{
     
    // Keep replacing n until is
    // an integer
    while ((int)Math.sqrt(n) ==
                Math.sqrt(n) && n > 1)
    {
        n = (int)(Math.sqrt(n));
    }
 
    // Keep replacing n until n
    // is divisible by i * i
    for(int i = (int)(Math.sqrt(n));
            i > 1; i--)
    {
        while (n % (i * i) == 0)
            n /= i;
    }
     
    // Print the answer
    System.out.println(n);
}
 
// Driver code
public static void main(String args[])
{
     
    // Given N
    int N = 20;
     
    // Function call
    minValue(N);
}
}
 
// This code is contributed by vikas_g


Python3




# Python3 program for the above approach
import math
 
# Function to reduce N to its minimum
# possible value by the given operations
def MinValue(n):
     
    # Keep replacing n until is
    # an integer
    while(int(math.sqrt(n)) ==
              math.sqrt(n) and n > 1):
        n = math.sqrt(n)
         
    # Keep replacing n until n
    # is divisible by i * i
    for i in range(int(math.sqrt(n)), 1, -1):
        while (n % (i * i) == 0):
            n /= i
             
    # Print the answer
    print(n)
 
# Driver code
n = 20
 
# Function call
MinValue(n)
 
# This code is contributed by virusbuddah_


C#




// C# implementation of the approach
using System;
 
class GFG{
     
// Function to reduce N to its minimum
// possible value by the given operations
static void minValue(int n)
{
     
    // Keep replacing n until is
    // an integer
    while ((int)Math.Sqrt(n) ==
                Math.Sqrt(n) && n > 1)
    {
        n = (int)(Math.Sqrt(n));
    }
     
    // Keep replacing n until n
    // is divisible by i * i
    for (int i = (int)(Math.Sqrt(n));
             i > 1; i--)
    {
        while (n % (i * i) == 0)
            n /= i;
    }
     
    // Print the answer
    Console.Write(n);
}
 
// Driver code
public static void Main()
{
     
    // Given N
    int N = 20;
     
    // Function call
    minValue(N);
}
}
 
// This code is contributed by vikas_g


Javascript




<script>
 
// Javascript program for above approach
 
// Function to reduce N to its minimum
// possible value by the given operations
function minValue(n)
{
 
    // Keep replacing n until is
    // an integer
    while (parseInt(Math.sqrt(n)) == Math.sqrt(n)
        && n > 1)
    {
        n = parseInt(Math.sqrt(n));
    }
 
    // Keep replacing n until n
    // is divisible by i * i
    for (var i = parseInt(Math.sqrt(n));
        i > 1; i--) {
 
        while (n % (i * i) == 0)
            n /= i;
    }
 
    // Print the answer
    document.write(n);
}
 
// Driver Code
 
// Given N
var N = 20;
 
// Function Call
minValue(N);
 
// This code is contributed by rutvik_56.
</script>


Output:

10

Time Complexity: O(N)
Auxiliary Space: O(1)

Feeling lost in the world of random DSA topics, wasting time without progress? It’s time for a change! Join our DSA course, where we’ll guide you on an exciting journey to master DSA efficiently and on schedule.
Ready to dive in? Explore our Free Demo Content and join our DSA course, trusted by over 100,000 neveropen!

RELATED ARTICLES

Most Popular

Dominic
32341 POSTS0 COMMENTS
Milvus
87 POSTS0 COMMENTS
Nango Kala
6709 POSTS0 COMMENTS
Nicole Veronica
11874 POSTS0 COMMENTS
Nokonwaba Nkukhwana
11937 POSTS0 COMMENTS
Shaida Kate Naidoo
6832 POSTS0 COMMENTS
Ted Musemwa
7091 POSTS0 COMMENTS
Thapelo Manthata
6783 POSTS0 COMMENTS
Umr Jansen
6785 POSTS0 COMMENTS