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move exercises, lecture examples, labs into subfolders

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Akbar Rahman
2023-10-13 16:19:51 +01:00
parent a602f20e01
commit 015b5d6a08
200 changed files with 2 additions and 2 deletions
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72
Lectures/LC19/swap.c Normal file
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#include <stdio.h>
#include <stdlib.h>
union number
{
double d;
float f;
long l;
int i;
unsigned short s;
unsigned char c[8];
};
int main(void)
{
/* Define variables and a union */
int my_i;
short my_s;
unsigned char tc;
union number mynum;
/* Prompt for use input ao a number whose bytes we are to swap */
printf ("\nPlease enter a number ");
scanf("%hi",&my_s); // hi is the format for a signed short
/* pop this number into our union */
mynum.s = my_s;
/* Show the present byte order */
printf ("\nThe bytes making up your number %hi are ",my_s);
printf ("%d %d %d %d %d %d %d %d ",mynum.c[0],mynum.c[1],mynum.c[2],mynum.c[3],mynum.c[4],mynum.c[5],mynum.c[6],mynum.c[7]);
/* We now swap the two lowest bytes (via an intermediate variable) */
tc = mynum.c[1];
mynum.c[1] = mynum.c[0];
mynum.c[0] = tc;
printf ("\nThe bytes making up your number are now ");
printf ("%d %d %d %d %d %d %d %d ",mynum.c[0],mynum.c[1],mynum.c[2],mynum.c[3],mynum.c[4],mynum.c[5],mynum.c[6],mynum.c[7]);
printf ("\nWhich corresponds to %d ",mynum.s);
// Repeat for an integer
/* Prompt for use input ao a number whose bytes we are to swap */
printf ("\nPlease enter a number [INTEGER] ");
scanf("%d",&my_i);
/* pop this number into our union */
mynum.i = my_i;
/* Show the present byte order */
printf ("\nThe bytes making up your number %d are ",my_i);
printf ("%d %d %d %d %d %d %d %d ",mynum.c[0],mynum.c[1],mynum.c[2],mynum.c[3],mynum.c[4],mynum.c[5],mynum.c[6],mynum.c[7]);
/* We now swap the 1st and 4th bytes (via an intermediate variable) */
tc = mynum.c[3];
mynum.c[3] = mynum.c[0];
mynum.c[0] = tc;
/* We now swap the 1st and 4th bytes (via an intermediate variable) */
tc = mynum.c[2];
mynum.c[2] = mynum.c[1];
mynum.c[1] = tc;
printf ("\nThe bytes making up your number are now ");
printf ("%d %d %d %d %d %d %d %d ",mynum.c[0],mynum.c[1],mynum.c[2],mynum.c[3],mynum.c[4],mynum.c[5],mynum.c[6],mynum.c[7]);
printf ("\nWhich corresponds to %d ",mynum.i);
return 0;
}