[程序]

procedure indexed (var seqfile : tseqfile; var index file : tindxfile);

const arsize = 100;

type tmparray = array [1..arsize] of tmpelement;

tmpfile = file of tmpelement;

var a : tmparray;

g,h : tmpfile;

n,recno : integer;

s : boolean;

procedure sort(var a : tmparray; n : integer); {將數(shù)組a的前n個(gè)元素按key遞增排序,本過程的過程體省略}

procedure combi(var f1,f2 : tmpfile); {將文件f1與數(shù)組a按關(guān)鍵字值從小到大合并于文件f2}

var i,j : integer;

begin i:=1; reset(f1); rewrite(f2);

while ________________ do

begin

if f1^.key <= a[i].key then

begin f2^:=f1^; get(f1) end

else

begin ___________ ; __________ end;

put (f2);

end;

while not eof(f1) do

begin f2^:=f1^; get(f1); put(f2) end;

for j:= i to n do

begin f2^:=a[j]; put(f2) end

end;

procedure gindex (var f:tmpfile);

begin rewrite (indexfile); reset(f);

while not eof(f) do

begin indexfile^:=f^.no;

put (indexfile); get(f)

end

end;

begin reset(seqfile); recno:=0;s:=true;

repeat n:=0 ;

while ____________ do

begin n:=n+1; a[n].key:=seqfile^.key;

recno:=recno+1;a[n].no:=recno;

get(seqfile)

end;

sort(a,n);

if s then combi(g,h)

else combi(h,g);

_______________________

until eof (seqfile);

if ________________ then gindex(g)

else gindex(h)

end;

    試題11

    [程序說明]

    本程序能從1至n(n<1000)的自然數(shù)中取r個(gè)數(shù)的所有組合,并按指定的格式輸出其結(jié)果.例如,n=5,r=3時(shí),共有10種組合(見下面左邊列表),而程序?qū)��?/FONT>