/
ch-1.c
37 lines (27 loc) · 937 Bytes
/
ch-1.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
/*
Challenge 119
TASK #1 - Swap Nibbles
Submitted by: Mohammad S Anwar
You are given a positive integer $N.
Write a script to swap the two nibbles of the binary representation of the
given number and print the decimal number of the new binary representation.
A nibble is a four-bit aggregation, or half an octet.
To keep the task simple, we only allow integer less than or equal to 255.
Example
Input: $N = 101
Output: 86
Binary representation of decimal 101 is 1100101 or as 2 nibbles (0110)(0101).
The swapped nibbles would be (0101)(0110) same as decimal 86.
Input: $N = 18
Output: 33
Binary representation of decimal 18 is 10010 or as 2 nibbles (0001)(0010).
The swapped nibbles would be (0010)(0001) same as decimal 33.
*/
#include <stdio.h>
#include <stdlib.h>
int main(int argc, char* argv[]) {
int n = 0;
if (argc == 2) n = atoi(argv[1]);
n = ((n >> 4) & 0x0f) | ((n << 4) & 0xf0);
printf("%d\n", n);
}