Right rotate functions for byte values : shift « Data Types « C++ Tutorial

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/*
Quote from: C++: A Beginner's Guide, Second Edition 

# Publisher: McGraw-Hill Osborne Media; 2 edition (December 3, 2003)
# Language: English
# ISBN-10: 0072232153
# ISBN-13: 978-0072232158
*/
 
#include <iostream> 
using namespace std; 
 
unsigned char rrotate(unsigned char val, int n); 
void show_binary(unsigned int u); 
 
int main() 
{ 
  char ch = 'T'; 
 
  cout << "Original value in binary:\n"; 
  show_binary(ch); 
 
  cout << "Rotating right 8 times:\n"; 
  for(int i=0; i < 8; i++) { 
    ch = rrotate(ch, 1); 
    show_binary(ch); 
  } 
 
  return 0; 
} 
 
// Right-rotate a byte n places. 
unsigned char rrotate(unsigned char val, int n) 
{ 
  unsigned int t; 
 
  t = val; 
 
  // First, move the value 8 bits higher. 
  t = t << 8; 
 
  for(int i=0; i < n; i++) { 
    t = t >> 1; 
 
    /* If a bit shifts out, it will be in bit 7 
       of the integer t. If this is the case, 
       put that bit on the left side. */ 
    if(t & 128)  
      t = t | 32768; // put a 1 on left end 
  } 
 
  /* Finally, move the result back to the 
     lower 8 bits of t. */ 
  t = t >> 8; 
 
  return t; 
} 
 
// Display the bits within a byte. 
void show_binary(unsigned int u) 
{ 
  int t; 
 
  for(t=128; t>0; t = t/2) 
    if(u & t) cout << "1 "; 
    else cout << "0 "; 
 
  cout << "\n"; 
}

Original value in binary:
0 1 0 1 0 1 0 0
Rotating right 8 times:
0 0 1 0 1 0 1 0
0 0 0 1 0 1 0 1
1 0 0 0 1 0 1 0
0 1 0 0 0 1 0 1
1 0 1 0 0 0 1 0
0 1 0 1 0 0 0 1
1 0 1 0 1 0 0 0
0 1 0 1 0 1 0 0