Key generation in Simplified DES in C.
#include<stdio.h>
int main()
{
int i, count=0, p8[8]={6,7,8,9,1,2,3,4};
int p10[10]={6,7,8,9,10,1,2,3,4,5};
char input[11], k1[10], k2[10], temp[11];
char LS1[5], LS2[5];
printf("Enter 10 Bits Input ::");
scanf("%s",input);
input[10]='\0';
for(i=0; i<10; i++)
{
count = p10[i];
temp[i] = input[count-1];
}
temp[i]='\0';
printf("\nYour p10 key is ::");
for(i=0; i<10; i++)
{ printf("%d,",p10[i]); }
printf("\nBits After p10 ::");
puts(temp);
for(i=0; i<5; i++)
{
if(i==4)
temp[i]=temp[0];
else
temp[i]=temp[i+1];
}
for(i=5; i<10; i++)
{
if(i==9)
temp[i]=temp[5];
else
temp[i]=temp[i+1];
}
printf("Output After LS-1 ::");
puts(temp);
printf("\nYour p8 Key is ::");
for(i=0; i<8; i++)
{ printf("%d,",p8[i]); }
for(i=0; i<8; i++)
{
count = p8[i];
k1[i] = temp[count-1];
}
printf("\nYour key k1 is :");
puts(k1);
}
OUTPUT
Enter 10 Bits Input :: Computer
Your p10 key is :: 6,7,8,9,10,1,2,3,4,5,
Bits After p10 :: ter
Output After LS-1 :: er
Your p8 Key is :: 6,7,8,9,1,2,3,4,
Your key k1 is : ompuer
