fork download 
  1. #include <stdio.h>
  2. #include <string.h>
  3. #include <stdlib.h>
  4.  
  5. void getdigits(char buf[], int n)
  6. {
  7.     while (n) {
  8. 		*buf++ = n % 10;
  9. 		n /= 10;
  10. 	}
  11. }
  12.  
  13. int compint(const void *a, const void *b)
  14. {
  15. 	return *(const char *)a - *(const char *)b;
  16. }
  17.  
  18. int is_vampire(char n[4], const char i[2], const char j[2])
  19. {
  20. 	char k[4] = { i[0], i[1], j[0], j[1] };
  21. 	qsort(k, 4, sizeof(k[0]), compint);
  22. 	qsort(n, 4, sizeof(n[0]), compint);
  23. 	return !memcmp(n, k, sizeof(k));
  24. }
  25.  
  26. int main()
  27. {
  28. 	for (int i = 10; i < 100; i++) {
  29. 		for (int j = 10; j < 100; j++) {
  30. 			int n = i * j;
  31. 			if (n < 1000)
  32. 				continue;
  33.  
  34. 			char ndigits[4];
  35. 			getdigits(ndigits, n);
  36.  
  37. 			char idigits[2];
  38. 			char jdigits[2];
  39. 			getdigits(idigits, i);
  40. 			getdigits(jdigits, j);
  41.  
  42. 			if (is_vampire(ndigits, idigits, jdigits))
  43. 				printf("%d * %d = %d\n", i, j, n);
  44. 		}
  45. 	}
  46.  
  47. 	return 0;
  48. }
  49.  
Success #stdin #stdout 0s 1832KB
comments (?)
stdin 
Standard input is empty
stdout 
15 * 93 = 1395
21 * 60 = 1260
21 * 87 = 1827
27 * 81 = 2187
30 * 51 = 1530
35 * 41 = 1435
41 * 35 = 1435
51 * 30 = 1530
60 * 21 = 1260
80 * 86 = 6880
81 * 27 = 2187
86 * 80 = 6880
87 * 21 = 1827
93 * 15 = 1395
https://ideone.com/2kzoIs
language:
C99 (gcc 8.3)
created:
11 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!