Compiling C program with OpenSSL

问题

I am new to Openssl. I have openssl 1.1.0e and libssl-dev installed on ubuntu 16.04. I am trying to run the example on this page in openssl documentation https://www.openssl.org/docs/man1.1.0/crypto/EVP_DigestInit.html.

I use the command

gcc example1.c -lssl -lcrypto 

to compile the program. But I get the following error Undefined Reference error

I have seen related questions on the forum but cannot find the solution. If anyone can help with pointing out the solution, it will be a great help.

来源：https://stackoverflow.com/questions/43644785/compiling-c-program-with-openssl