linking problem using openssl/des.h

I am using Des to encrypt my data but when i want to compile my code. it is giving linkage problem can anyone solve my problem ..............

code is here
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#include <stdio.h>
#include <openssl/des.h>

/* Use libdes to encrypt one input under one key, then show result. */
typedef struct _des_ctx
  {
    unsigned long int encrypt_subkeys[32];
    unsigned long int  decrypt_subkeys[32];
  }
des_ctx[1];

int  main(int argc, char **argv){

  int i;
  const_des_cblock key[]={0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef};
  const_des_cblock plaintext[]={0xab, 0xcd, 0xef, 0xab, 0xcd, 0xef, 0xab, 0xcd};
  des_cblock ciphertext[8];
  des_cblock recoverd[8];
  des_ctx context;
  //*     * Set up the DES encryption context *
  des_set_key((void *)context, (void *)key);
  //     * Encrypt the plaintext *
  des_ecb_encrypt((void *)context, (void *)plaintext, (void *)ciphertext,0);
  for(i = 0; i < 8; i++)
    printf("%2.2x", recoverd[i]);
  printf("\n");      
  //     * To recover the orginal plaintext from ciphertext use: *
  des_ecb_encrypt((void *)context, (void *)ciphertext, (void *)recoverd, 1);
  for(i = 0; i < 8; i++)
    printf("%2.2x", recoverd[i]);
  printf("\n");      
}
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and linkage error is as follow

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[siayubi@localhost work]$
/tmp/cclvFxUi.o: In function `main':
/tmp/cclvFxUi.o(.text+0x62): undefined reference to `des_set_key'
/tmp/cclvFxUi.o(.text+0x7b): undefined reference to `des_ecb_encrypt'
/tmp/cclvFxUi.o(.text+0xdd): undefined reference to `des_ecb_encrypt'
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