>>3
使用言語：maxima

P1():=(f:openw("test.txt"),
printf(f,"Computer1Programing2Communication3Electro4~%"),
close(f)
);

P2():=(fin:openr("test.txt"),fout:openw("sample.txt"),
printf(fout,"~a~%",sreverse(readline(fin))),
close(fin),
close(fout)
);

P3():=(fin:openr("sample.txt"),
text:readline(fin),
for v in charlist(text) do if uppercasep(v) then printf(true, "~a", v),
close(fin),
print("")
);

P1();P2();P3();