[目前未找到题目]扩展KMP模板

procedure build_next;
begin
    lena:=length(a);lenb:=length(b);
    next[]:=lenb;next[]:=lenb-;
    for i:= to lenb- do if b[i]<>b[i+] then
    begin
        next[]:=i;break;
    end;
    k:=;
    for i:= to lenb-1 do
    begin
        p:=k+next[k]-;L:=next[i-k];
        if i+L<=p then next[i]:=L else
        begin
            j:=p-i+;
            if j< then j:=;
            while (i+j<lenb)and(a[i+j]=b[j]) do inc(j);
            next[i]:=j;k:=i;
        end;
    end;
end;

procedure build_ex;
begin
    if lena<lenb then minlen:=lena else minlen:=lenb;
    ex[]:=minlen;
    for i:= to minlen-1 do if a[i]<>b[i] then
    begin
        ex[]:=i;break;
    end;
    k:=;
    for i:= to lena-1 do
    begin
        p:=k+ex[k]-;L:=next[i-k];
        if i+L<=p then ex[i]:=L else
        begin
            j:=p-i+;
            if j< then j:=;
            while (i+j<lena)and(j<lenb)and(a[i+j]=b[j]) do inc(j);
            ex[i]:=j;k:=i;
        end;
    end;
end;