Cây trong passcall cài đặc bằng con trỏ uses crt; const max=30; type cay=^tree; tree=record data:integer; lnext:cay; rnext:cay; end; elementtype=cay; var i, x:integer; ch:char; t:cay; {========tao rong =========} procedure taorong(var t:cay); begin t:=nil; end; {====== kiem tra rong =======} function ktrong(var t:cay):boolean; begin ktrong:=(t=nil); end; {=========== xen ============} procedure xen(var t:cay;x:integer); begin if t=nil then begin new(t); t^.rnext:=nil; t^.lnext:=nil; t^.data:=x; end else if x>t^.data then xen(t^.rnext,x) else xen(t^.lnext,x); end; {===== nhap =========} procedure nhap(var t:cay); var n,m,x:integer; begin taorong(t); write('nhap vao so nut cua cay:'); readln(n); for i:=1 to n do begin write('nhap vao nut thu ',i,':'); readln(m); xen(t,m); end; end; {========== xuat ===========} procedure tientu(t:cay); begin if t<> nil then begin write(t^.data); tientu(t^.lnext); tientu(t^.rnext); end; end; {========== xuat ===========} Procedure trung(var t:cay); begin if t<> nil then begin trung(t^.lnext); write(t^.data:4); trung(t^.rnext); end; end; {============ Xuat ===========} Procedure hau(var t:cay); begin if t<> nil then begin hau(t^.lnext); hau(t^.rnext); write(t^.data:4); end; end; {====== chieu cao cua cay=======} function mac(a,b:integer):integer; begin if a<b then mac:=b else mac:=a; end; {=============} function chieucao(t:cay):integer; begin if t=nil then chieucao:=0 else begin if (t^.lnext=nil) and (t^.rnext=nil) then chieucao:=0 else chieucao:=mac(chieucao(t^.lnext), chieucao(t^.rnext))+1; end; end; {==== xoa nut nho nhat =======} function xoa(var t:cay):integer; begin if t^.lnext=nil then begin xoa:=t^.data; t:=t^.rnext; end else xoa:=xoa(t^.lnext); end; {====== xoa mot nut =========} procedure xoa1(var t:cay;x:integer); begin if t<> nil then begin if x>t^.data then xoa1(t^.rnext,x) else if x<t^.data then xoa1(t^.lnext,x) else if (t^.lnext=nil) and (t^.rnext=nil) then t:=nil else if t^.lnext=nil then t:=t^.rnext else if t^.rnext=nil then t:=t^.lnext else t^.data:=xoa(t^.rnext); end; end; {====== tong so nut ========} function tong(var t:cay):integer; begin if t=nil then tong:=0 else tong:=tong(t^.lnext)+tong(t^.rnext)+1; end; {===== in nut la ==========} procedure nutla(t:cay); begin if t<> nil then begin if (t^.lnext=nil) and (t^.rnext=nil) then write(t^.data:4); nutla(t^.lnext); nutla(t^.rnext); end; end; {====== nut le cua cay =========} procedure nutle(var t:cay); begin if t<> nil then begin if odd(t^.data) then write(t^.data:4); nutle(t^.lnext); nutle(t^.rnext); end; end; {====== nut trung gian ========} procedure trunggian(t:cay); begin if t<> nil then begin if (t^.lnext<> nil) or (t^.rnext<>nil) then write(t^.data:4); trunggian(t^.lnext); trunggian(t^.rnext); end; end; {===== in ra nut co mot con =====} procedure nutcon(var t:cay); begin if t<> nil then begin if (t^.lnext=nil) and (t^.rnext<>nil)or ((t^.rnext<>nil) and (t^.rnext=nil)) then begin write(t^.data:4); nutcon(t^.lnext); nutcon(t^.rnext); end else write('khong co'); end; end; {=== tim kien nut cau cay =======} function tim(x:integer;t:cay):boolean; begin if t<> nil then if t^.data=x then write('nut duoc tim thay trong cay') else if t^.data>x then tim:=tim(x,t^.lnext) else tim:=tim(x,t^.rnext) else write('khong tim thay mut trong cay'); end; {================chuong trinh chinh ========} begin clrscr; nhap(t); write(' nut cua cay la; '); tientu(t);writeln;readln; write('tong so nut cua cay la : ',tong(t)); writeln; write(' nut la cua cay la : '); nutla(t);writeln; write(' nut le cua cay la : '); nutle(t);writeln; write(' nut trung gian cua cay la : '); trunggian(t); writeln; write('nut chi co mot con la: '); nutcon(t);writeln; write('chieu cao cau cay la: ',chieucao(t)); writeln; write('nhap vao nut ban muon tim : ');readln(x); tim(x,t);writeln; write('ENTER de xoa nut nho nhat');readln; write(' nut sau khi xoa la : '); xoa(t); tientu(t);writeln; write('nhap vao nut ban muong xoa : ');readln(x); xoa1(t,x); write('nut con lai trong cay la: '); tientu(t);writeln; readln; end. . Cây trong passcall cài đặc bằng con trỏ uses crt; const max=30; type cay=^tree; tree=record data:integer; lnext:cay; rnext:cay; end; elementtype=cay; var. taorong(var t:cay); begin t:=nil; end; {====== kiem tra rong =======} function ktrong(var t:cay):boolean; begin ktrong:=(t=nil); end; {=========== xen ============} procedure xen(var t:cay;x:integer); begin if. then write(t^.data:4); trunggian(t^.lnext); trunggian(t^.rnext); end; end; {===== in ra nut co mot con =====} procedure nutcon(var t:cay); begin if t<> nil then begin if (t^.lnext=nil) and (t^.rnext<>nil)or