Given an integer n , you have to print all the ways in which n can be represented as sum of positive integers

#define ARR_SIZE 100
#include<stdio.h>


void printArray(int arr[], int arr_size)
{
int i;
for (i = 0; i < arr_size; i++)
printf("%d ", arr[i]);
printf("\n");
}


/* The function prints all combinations of numbers 1, 2, ...n
that sum up to n. i is used in recursion keep track of index in arr[] where next
element is to be added. Initital value of i must be passed as 0 */
void printCompositions(int n,int m ,int i)
{

/* array must be static as we want to keep track
of values stored in arr[] using current calls of
printCompositions() in function call stack*/
static int arr[ARR_SIZE];

if (n == 0)
{
printArray(arr, i);
}
else if(n > 0)
{
int k;
for (k = 1; k <= m; k++)
{
arr[i]= k;
printCompositions(n-k,m, i+1);
}
}
}


/* Driver function to test above functions */
int main()
{
int n = 5;
printf("Differnt compositions formed by 1, 2 , 3 , 4 and 5  %d are\n", n);
printCompositions(n,n, 0);
getchar();
return 0;
}

Time Complexity O(n^m) Exponential
Space Complexity O(m)
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