Program to print N minimum elements from list of integers

Difficulty Level : Basic
Last Updated : 25 Jan, 2021

Given a list of integers, the task is to generate another list with N minimum elements.

Examples:

Input: {23, 1, 6, 2, 90}
Output: {1, 2}

Input: {34, 21, 56, 42, 89, 90, -1}
Output: {-1, 21}

Approach: The idea is to use the concept used in Find the smallest and second smallest elements in an array.

First, find the smallest number in the given list.
Then add that current minimum element to another list that will contain the N minimum elements.
Remove the current minimum element from the given list.
Continue with the same process until the N minimum elements are found.

Below is the implementation of the above approach:

C++

// C++ program to find N 
// minimum elements
#include <bits/stdc++.h>
using namespace std;
 
void Nminelements(vector<int>list1, int N)
{
    vector<int> final_list;
    int n = list1.size();
    for (int i = 0; i < N; i++) 
    {
        int min1 = 9999999;
        for (int j = 0; j < n; j++)
        {
            if (list1[j] < min1)
                min1 = list1[j];
        }
         
        // remove minimum element 
        // from list so that it do
        // not come in calculation again         
        list1.erase(remove(list1.begin(), 
                           list1.end(), min1), 
                           list1.end());
        final_list.push_back(min1);
    }
    for(int i = 0; i < final_list.size(); i++)
    cout << final_list[i] << " ";
} 
 
// Driver code
int main()
{
    vector<int> list1 = {4, 78, 34, 10, 
                         8, 21, 11, 231};
    int N = 2;
    Nminelements(list1, N);
}
 
// This code is contributed by Subhadeep

Python3

# Python3 program to find N minimum elements
def Nminelements(list1, N):
    final_list =[];
  
    for i in range(0, N):    
        min1 = 9999999;
          
        for j in range(len(list1)):      
            if list1[j]<min1:
                min1 = list1[j];
 
        # remove minimum element from list so 
        # that it do not come in calculation again         
        list1.remove(min1);
        final_list.append(min1)
          
    print(final_list)
  
# Driver code
list1 = [4, 78, 34, 10, 8, 21, 11, 231];
N = 2;
Nminelements(list1, N)

C#

// C# program to find N
// minimum elements
using System;
using System.Collections;
 
class GFG{
 
static void Nminelements(ArrayList list1, int N)
{
    ArrayList final_list = new ArrayList();
 
    for(int i = 0; i < N; i++) 
    {
        int min1 = 9999999;
        for(int j = 0; j < list1.Count; j++)
        {
            if ((int)list1[j] < min1)
                min1 = (int)list1[j];
        }
         
        // Remove minimum element
        // from list so that it do
        // not come in calculation again
        list1.Remove(min1);
 
        final_list.Add(min1);
    }
    for(int i = 0; i < final_list.Count; i++)
        Console.Write(final_list[i] + " ");
}
 
// Driver code
public static void Main()
{
    ArrayList list1 = new ArrayList(){ 4, 78, 34, 10, 
                                       8, 21, 11, 231 };
    int N = 2;
     
    Nminelements(list1, N);
}
}
 
// This code is contributed by chitranayal

Output:

4 8

Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course.

My Personal Notes

Related Articles

C++

Python3

C#