Write a Merkle-Hellman cryptosystem in C++ **Please don\'t just copy/paste some

Question

Write a Merkle-Hellman cryptosystem in C++
**Please don't just copy/paste some code, if you don't know, then don't answer**
Information on cipher can be found here:
https://en.wikipedia.org/wiki/Merkle%E2%80%93Hellman_knapsack_cryptosystem

Instructions for program:

Your program will need to get its input from a file in the following format

First line is an integer saying how many test cases are in the input file

A line containing the plaintext to be encrypted.

A line containing a single integer with the number of items in the sequence

A line containing the entire sequence.

Explanation / Answer

#include <stdio.h>

#include <math.h>

#include <stdlib.h>

#include <time.h>

#include <conio.h>

int gcd( int a, int b)

{

while(a!= b)

{

if(a > b)

m =a - b;

else

b = b -a;

}

return (a); //a or b is GCD

}

void sort(int arr[])

{

int x, j, temp ;

for ( x = 0 ; x <= 7 ; x++ )

{

for ( j = x + 1 ; j <= 8 ; j++ )

{

if ( arr[x] > arr[j] )

{

temp = arr[x] ;

arr[x] = arr[j] ;

arr[j] = temp ;

}

}

}

}

int sum(int m[])

{

int x, sum=0;

for (x=0; x<8; x++)

{

sum = sum + m[i];

}

return(sum);

}

int main()

{

printf(" Initialising the super-increasing sequence ");

int w[8],i,j,qt,q,r;

int b[8],a[8];

int c=0;

for(i=0;i<9;i++)

srand(time(NULL));

for(i=0;i<8;i++)

w[i]=rand()%1000;

qt=sum(w);

q=rand()%10000;

while(q<qt)

{

q=rand()%10000;

}

sort(w);

printf(" The super-increasing sequence is: ");

for(j=0;j<8;j++)

printf("%d ",w[j]);

printf(" The value of sigma W is %d",qt);

printf(" The value of q chosen is %d ",q);

rep:r=rand();

while(gcd(q,r)!=1)

{

r=rand();

}

if(q<r) goto rep;

printf(" The value of r chosen is %d ",r);

for(i=0;i<8;i++)

{

b[i]=(r*w[i])%q;

}

printf(" The public key beta is ");

for(j=0;j<8;j++)

printf("%d ",b[j]);

printf(" Enter the 8-bit ");

for(i=0;i<8;i++)

scanf("%d",&a[i]);

printf(" The Encrypted is ");

for(i=0;i<8;i++)

c+=(a[i]*b[i]);

printf("%d ",c);

scanf("%d");

return 0;

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