9 May 2025   9:29:27.683 PM

rot13_test()
  Fortran90 version.
  Test rot13().

  call S_TO_ROT13 ( S1, S2 ).

  -------------------S1-------------------  -------------------S2-------------------

  "abcdefghijklmnopqrstuvwxyz"              "nopqrstuvwxyzabcdefghijklm"            
  "Cher"                                    "Pure"                                  
  "James Thurston Howell III"               "Wnzrf Guhefgba Ubjryy VVV"             
  "The bill is $1,205,837.49 so pay now!"   "Gur ovyy vf $6,750,382.94 fb cnl abj!" 

  call ROT13 ( S1, S2 ).
  call ROT13 ( S2, S3 ).

  -------------------S1-------------------  -------------------S3-------------------

  "abcdefghijklmnopqrstuvwxyz"              "abcdefghijklmnopqrstuvwxyz"            
  "Cher"                                    "Cher"                                  
  "James Thurston Howell III"               "James Thurston Howell III"             
  "The bill is $1,205,837.49 so pay now!"   "The bill is $1,205,837.49 so pay now!" 

ROT13_TEST
  Normal end of execution.

 9 May 2025   9:29:27.683 PM