How to verify a checksum using one command line?

Suppose I type and run the following command: sha256sum ubuntu-18.04.1-desktop-amd64.iso After a delay, this outputs the following: 5748706937539418ee5707bd538c4f5eabae485d17aa49fb13ce2c9b70532433 ubuntu-18.04.1-desktop-amd64.iso Then, I realize that I should have typed the following command to more rapidly assess whether the SHA‐256 hash matches: sha256sum ubuntu-18.04.1-desktop-amd64.iso | grep 5748706937539418ee5707bd538c4f5eabae485d17aa49fb13ce2c9b70532433 Is there a way to act on the first output without using the sha256sum command to verify the checksum a second time (i.e., to avoid the delay that would be caused by doing so)? Specifically: 1. I'd like to know how to do this using a command that does not require copy and pasting of the first output's checksum (if it's possible). 2. I'd like to know the simplest way to do this using a command that does require copy and pasting of the first output's checksum. (Simply attempting to use grep on a double‐quoted pasted checksum (i.e., as a string) doesn't work.)