[C Programming #3] Print all combinations of given array with given size

Problem: Print all possible combinations of given array with given combination size limit.

Input:
array: 10 11 12 13 14
combination size: 3

Output:
10 11 12
10 12 13
10 13 14
11 12 13
11 13 14
12 13 14

Program:

1. #include<stdio.h>
2. 
   
3. void print_combinations(int a[], int n, int r) {
4. int i,j,k;
5. for (i = 0; i <= n-r; i++) {
6. for (j = i+1; j+r-1 <= n; j++) {
7. printf("%d\t", a[i]);
8. for (k = 0; k < r-1; k++)
9. printf("%d\t", a[j+k]);
10. printf("\n");
11. }
12. printf("\n");
13. }
14. }
15. 
    
16. int main()
17. {
18.   int a[] ={10,11,12,13,14};
19.   int n=sizeof(a)/sizeof(a[0]);
20.   print_combinations(a, n, 3);
21.  
22. return 0;
23. }