Takes me back to my Uni years (late 90s) were at one point we had do implement a (DOS based) spreadsheet program, all with stack based equation parsing and cell

Takes me back to my Uni years (late 90s) were at one point we had do implement a (DOS based) spreadsheet program, all with stack based equation parsing and cell references. It was a really cool project which allowed me to understand the insides of spreadsheets.