Bitwise shifting array of char’s

by

You have to shift and compare elementwise.

for(i = 0; i < len; ++i)
    array[i] >>= 3;

for example. If you want to move the bits shifted out of one element to the next, it’s more complicated, say you’re shifting right, then

unsigned char bits1 = 0, bits2 = 0;
for(i = len-1; i >= 0; --i) {
    bits2 = array[i] & 0x07;
    array[i] >>= 3;
    array[i] |= bits1 << 5;
    bits1 = bits2;
}

traversing the array in the other direction because you need the bits from the next higher slot.

More Related Contents:

  1. What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?
  2. Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C
  3. Are the shift operators () arithmetic or logical in C?
  4. How can I multiply and divide using only bit shifting and adding?
  5. What is Bit Masking?
  6. What is CHAR_BIT?
  7. Find most significant bit (left-most) that is set in a bit array
  8. Fast computing of log2 for 64-bit integers
  9. Bitfield manipulation in C
  10. Fastest way to clamp a real (fixed/floating point) value?
  11. What’s bad about shifting a 32-bit variable 32 bits?
  12. Casting float to int (bitwise) in C
  13. What does the statement if (counter & (1
  14. Compute fast log base 2 ceiling
  15. Finding consecutive bit string of 1 or 0
  16. warning: left shift count >= width of type
  17. set the m-bit to n-bit [closed]
  18. Bitshift and integer promotion?
  19. Unexpected C/C++ bitwise shift operators outcome
  20. Encoding int value as an IEEE-754 float (binary32)
  21. C reverse bits in unsigned integer
  22. How to define and work with an array of bits in C?
  23. Implementing Logical Right Shift in C
  24. Algorithm to generate bit mask
  25. Check if a number is non zero using bitwise operators in C
  26. How to replace bits in a bitfield without affecting other bits using C
  27. Decimal to Binary
  28. C Programming – XOR Bitwise Operation
  29. How to implement Bitcount using only Bitwise operators?
  30. Order of fields when using a bit field in C

Leave a Comment