SHA-256 is the recommended stronger alternative to SHA-1. See FIPS PUB 180-4 for implementation details.

Either by using a dedicated library or implementing the algorithm in your language, show that the SHA-256 digest of the string "Rosetta code" is: 764faf5c61ac315f1497f9dfa542713965b785e5cc2f707d6468d7d1124cdfcf

(ql:quickload 'ironclad)
(defun sha-256 (str)
  (ironclad:byte-array-to-hex-string
    (ironclad:digest-sequence :sha256 
                              (ironclad:ascii-string-to-byte-array str))))
 
(sha-256 "Rosetta code")