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  1. #include <stdio.h>
  2.  
  3. unsigned compress_maskA9_reversed1(unsigned x)
  4. {
  5.     // result: he00 | 00ca;
  6.     return (((x & 0x09)*0x88000000 >> 28) & 0x0C) | (((x & 0xA0)*0x04800000) >> 30);
  7. }
  8.  
  9. unsigned compress_maskA9_reversed2(unsigned x)
  10. {
  11.     return ((x & 0xA8)*0x12400000 >> 29) | (x & 0x01) << 3; // result: 0eca | h000
  12. }
  13.  
  14. int main(void) {
  15. 	// your code goes here
  16. 	unsigned i;
  17. 	printf("Start\n");
  18. 	for (i = 0; i < 256; ++i)
  19. 	{
  20. 		// abcdefgh -> 0000heca
  21. 		unsigned r = (i & 0x01) << 3 | (i & 0x08) >> 1 | (i & 0x20) >> 4 | (i >> 7);
  22. 		if (compress_maskA9_reversed1(i) != r)
  23. 		{
  24. 			printf("(1) Error at %u\n", i);
  25. 		}
  26. 		if (compress_maskA9_reversed2(i) != r)
  27. 		{
  28. 			printf("(2) Error at %u\n", i);
  29. 		}
  30. 	}
  31. 	printf("Finished\n");
  32.  
  33. 	return 0;
  34. }
  35.  
Success #stdin #stdout 0s 2052KB
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Start
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https://ideone.com/PYUkty
language:
C (gcc 8.3)
created:
10 years ago
visibility:
public

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