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# Random list of M non-negative integers whose sum is N

• Last Updated : 19 May, 2021

Given two integers M and N, the task is to create a list of M non-negative integers whose sum is N. In case when more than one list is possible, find any one.
Examples:

Input: M = 4, N = 8
Output: 1 3 3 1
1 + 3 + 3 + 1 = 8
Input: M = 5, N = 3
Output: 0 1 1 0 1

Approach: To get a complete random list of integers, create an array of size M where every element is initialised with 0. Now run a loop from 0 to N – 1 and increment any randomly chosen element from the array by 1 using the rand() function. This way, sum of the resuntant list will be N.
Below is the implementation of the above approach:

## C++

 `// C++ implementation of the approach``#include ``using` `namespace` `std;` `// Utility function to print the``// elements of an array``void` `printArr(``int` `arr[], ``int` `n)``{``    ``for` `(``int` `i = 0; i < n; i++)``        ``cout << arr[i] << ``" "``;``}` `// Function to generate a list of``// m random non-negative integers``// whose sum is n``void` `randomList(``int` `m, ``int` `n)``{` `    ``// Create an array of size m where``    ``// every element is initialized to 0``    ``int` `arr[m] = { 0 };``    ``srand``(``time``(0));` `    ``// To make the sum of the final list as n``    ``for` `(``int` `i = 0; i < n; i++) {` `        ``// Increment any random element``        ``// from the array by 1``        ``arr[``rand``() % m]++;``    ``}` `    ``// Print the generated list``    ``printArr(arr, m);``}` `// Driver code``int` `main()``{``    ``int` `m = 4, n = 8;` `    ``randomList(m, n);` `    ``return` `0;``}`

## Java

 `// Java implementation of the approach``class` `GFG``{``    ` `// Utility function to print the``// elements of an array``static` `void` `printArr(``int` `arr[], ``int` `n)``{``    ``for` `(``int` `i = ``0``; i < n; i++)``        ``System.out.print(arr[i] + ``" "``);``}` `// Function to generate a list of``// m random non-negative integers``// whose sum is n``static` `void` `randomList(``int` `m, ``int` `n)``{` `    ``// Create an array of size m where``    ``// every element is initialized to 0``    ``int` `arr[] = ``new` `int``[m];``    ` `    ``// To make the sum of the final list as n``    ``for` `(``int` `i = ``0``; i < n; i++)``    ``{` `        ``// Increment any random element``        ``// from the array by 1``        ``arr[(``int``)(Math.random() * m)]++;``    ``}` `    ``// Print the generated list``    ``printArr(arr, m);``}` `// Driver code``public` `static` `void` `main(String args[])``{``    ``int` `m = ``4``, n = ``8``;` `    ``randomList(m, n);``}``}` `// This code is contributed by Arnab Kundu`

## Python3

 `# Python3 implementation of the approach``from` `random ``import` `randint` `# Utility function to print the``# elements of an array``def` `printArr(arr, n) :` `    ``for` `i ``in` `range``(n) :``        ``print``(arr[i], end ``=` `" "``);` `# Function to generate a list of``# m random non-negative integers``# whose sum is n``def` `randomList(m, n):` `    ``# Create an array of size m where``    ``# every element is initialized to 0``    ``arr ``=` `[``0``] ``*` `m;``    ` `    ``# To make the sum of the final list as n``    ``for` `i ``in` `range``(n) :` `        ``# Increment any random element``        ``# from the array by 1``        ``arr[randint(``0``, n) ``%` `m] ``+``=` `1``;` `    ``# Print the generated list``    ``printArr(arr, m);` `# Driver code``if` `__name__ ``=``=` `"__main__"` `:` `    ``m ``=` `4``; n ``=` `8``;` `    ``randomList(m, n);` `# This code is contributed by AnkitRai01`

## C#

 `// C# implementation of the approach``using` `System;` `class` `GFG``{``    ` `// Utility function to print the``// elements of an array``static` `void` `printArr(``int` `[]arr, ``int` `n)``{``    ``for` `(``int` `i = 0; i < n; i++)``        ``Console.Write(arr[i] + ``" "``);``}` `// Function to generate a list of``// m random non-negative integers``// whose sum is n``static` `void` `randomList(``int` `m, ``int` `n)``{` `    ``// Create an array of size m where``    ``// every element is initialized to 0``    ``int` `[] arr = ``new` `int``[m];``    ` `    ``// To make the sum of the final list as n``    ``for` `(``int` `i = 0; i < n; i++)``    ``{` `        ``// Increment any random element``        ``// from the array by 1``        ``Random rnd = ``new` `Random();` `        ``arr[rnd.Next(0, n) % m]++;``    ``}` `    ``// Print the generated list``    ``printArr(arr, m);``}` `// Driver code``public` `static` `void` `Main()``{``    ``int` `m = 4, n = 8;` `    ``randomList(m, n);``}``}` `// This code is contributed by Mohit kumar`

## Javascript

 ``
Output:

`1 3 3 1`

Time Complexity: O(max(M, N))

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