Mình viết theo từng câu nha

Program vidu;

Uses Crt;

Var: array[0..100] of integer;

i, h,j,x,k,l,N: integer;

BEGIN

clrscr

Write('So phan tu cua a la:');Readln(N);

 for i:=0 to N do Readln(a[i]);

(**)

Readln;

END.

Chen may doan sau vao (**)

a)

Write('Nhap so k:'); Readln(k);

i:=0;

While i<= N do 

Begin

if k = a[i] then Writeln('Vi tri cua k tai a[',i,']');

i:=i+1;

End;

b) 

Writeln('Mang truoc khi chen');

For i:= 1 to N do Write(a[i]);

Writeln;

Write('Nhap vi tri ban muon chen vao'); Readln(k);

Write('Nhap gia tri ban muon chen vao');Readln(x);

for i:= N downto k+1 do

Begin

a[i]:= a[i+1];

End;

for i:= 0 to k-1 do

Begin

a[i]:=a[i-1];

End;

a[k]:= x;

for i:= 1 to N do Write(a[i]);

c) Tang dan:

for i:=0 to N - 1 do

for j:=1 to N do

if a[i] > a[j] then 

Begin

x:=a[i];

a[i]:=a[j];

a[j]:=x;

End;

Writeln('Mang saukhi sap xep la')

For i:=1 to n do Write(a[i],' ');

Giam dan: dao nguoc du minh gach chan la duoc

d) Day tang dan

Writeln('Nhap gia tri x:'); Readln(x);

for l:=1 to n do

Begin

if (x >= a [l]) and (x =< a[l+1]) then 

Begin

i:=l

for h:= N downto i+1 do

Begin

a[h]:= a[h+1];

End;

for h:= 0 to i-1 do

Begin

a[h]:=a[h-1];

End;

a[i]:=x;

End;

Day giam dan 

Thay dong in dam thanh

if (x <=a[i]) and (x>=a[i+1]) then...