include "cowgol.coh";
include "strings.coh";

sub Contains(s1: [uint8], s2: [uint8]): (r: uint8) is
    r := 0;
    while [s1] != 0 loop
        var a := s1;
        var b := s2;
        while [b] != 0 and [a] == [b] loop
            a := @next a;
            b := @next b;
        end loop;
        if [b] == 0 then
            r := 1;
            return;
        end if;
        s1 := @next s1;
    end loop;
end sub;

sub LCS(s1: [uint8], s2: [uint8], outbuf: [uint8]) is
    if StrLen(s1) < StrLen(s2) then
        var temp := s1;
        s1 := s2;
        s2 := temp;
    end if;

    var maxlen := StrLen(s2);
    var length := maxlen;
    while length > 0 loop
        var start: intptr := 0;
        while start + length <= maxlen loop
            MemCopy(s2 + start, length, outbuf);
            [outbuf + length + 1] := 0;
            if Contains(s1, outbuf) != 0 then
                return;
            end if;
            start := start + 1;
        end loop;
        length := length - 1;
    end loop;
    [outbuf] := 0;
end sub;

var lcs: uint8[64];
LCS("thisisatest", "testing123testing", &lcs[0]);
print(&lcs[0]);
print_nl();