> with(numtheory):
Warning, the protected name order has been redefined and unprotected
> 
> ## Susthma kruptografhshs RSA
> 
> gen_key:=proc(digits)
> local R1,R2,p,q,length,n,e,d,phin,tmp,i:
> irem(digits,2,'length'):
> R1:=rand(10^(digits-1),10^digits):
> p:=nextprime(R1()):
> q:=nextprime(R1()):
> n:=p*q:
> R2:=rand(4..100):
> phin:=phi(n):
> e:=R2():
> for i from 1 while igcd(e,phin)>1 do
>   e:=R2()
> end do:
> igcdex(e,phin,'d','tmp'):
> RETURN([[n,d],[n,e]]):
> end proc:
> 
> ## Kruptografhsh
> encrypt:=proc(m,public)
> local c,n,e:
> n:=public[1]:
> e:=public[2]:
> c:=m&^e mod n:
> RETURN(c):
> end proc:
> 
> ## Apokruptografhsh
> decrypt:=proc(c,private)
> local n,d,m:
> n:=private[1]:
> d:=private[2]:
> m:=c&^d mod n:
> RETURN(m):
> end proc:
> 
> key:=gen_key(20);
        key := [[4214854681266378492006369749407863773, 

          1978401176920953167773167246032780689], 

          [4214854681266378492006369749407863773, 49]]
> private:=key[1];
      private := [4214854681266378492006369749407863773, 

        1978401176920953167773167246032780689]
> public:=key[2];
     public := [4214854681266378492006369749407863773, 49]
> m:=1234567890987654321;
                    m := 1234567890987654321
> igcd(m,public[1]);
                               1
> ciphertext:=encrypt(m,public);
       ciphertext := 871949470675522843202481294367281324
> decrypt(ciphertext,private);
                      1234567890987654321
>