a) var a:array[1..1000] of integer;

i,k:integer;

p:longint;

begin

write('k = ');readln(k);

p:=1;

for i:=1 to k do

begin

write('Nhap so thu ',i,' = ');readln(a[i]);

if a[i]<30 then p:=p*a[i];

end;

write('Tich la ',p);

readln

end.

b) 

var a:array[1..1000] of integer;

i,k:integer;

s:longint;

begin

write('k = ');readln(k);

for i:=1 to k do

begin

write('Nhap so thu ',i,' = ');readln(a[i]);

if a[i]<100 then s:=s+a[i];

end;

write('Tong la ',s);

readln

end.

uses crt;

var n,i,k,dem:integer;

a:array[1..100]of integer;

begin

clrscr;

write('Nhap n='); readln(n);

for i:=1 to n do 

  begin

write('A[',i,']='); readln(a[i]);

end;

dem:=0;

for i:=1 to n do 

  if a[i] mod 2=0 then inc(dem);

writeln('So phan tu chan trong day so la: ',dem);

write('Nhap so k='); readln(k);

kt:=0;

for i:=1 to n do 

  if a[i]=k then kt:=i;

if kt=0 then writeln('Khong co phan tu nao trong day bang ',k)

else writeln('Trong day co phan tu bang ',k);

readln;

end.

program bai_2;

uses crt;

var a:array[1..100]of byte;

n,i,j,tam,vt,vt2,x,x2,k,ch:byte;

procedure yc1;

begin

  for i:=1 to n do

  begin

    write('nhap phan tu a[',i,']:');readln(a[i]);

  end;

  for i:=1 to n do write(a[i]:3);

end;

procedure yc2;

begin

  for i:=1 to n do

  begin

    write('nhap phan tu a[',i,']:');readln(a[i]);

  end;

  for i:=1 to n-1 do

  for j:=i+1 to n do

  if a[i]>a[j] then

  begin

    tam:=a[i];

    a[i]:=a[j];

    a[j]:=tam;

  end;

  writeln('mang a:');for i:=1 to n do write(a[i]:3);

end;

procedure yc3;

begin

    for i:=1 to n do

    begin

      write('nhap phan tu a[',i,']:');readln(a[i]);

    end;

    write('nhap so x:');readln(x);

    for i:=n downto 1 do

    if a[i]=x then vt:=i;if a[i]=x then writeln('vi tri cua ',x,' trong mang a la:',vt);writeln;

    if a[i]<>x then writeln('khong tim thay ',x,' trong day so tren');writeln;

end;

procedure yc4;

begin

  for i:=1 to n do

  begin

   write('nhap phan tu a[',i,']:');readln(a[i]);

  end;

  write('nhap so x2:');readln(x2);

  for i:=n downto 1 do

    if a[i]=x2 then vt2:=i;if x>0 then

    begin

      for i:=vt2 to n-1 do a[i]:=a[i+1];

      for i:=1 to n-1 do write(a[i]:3);

    end

  else  if a[i]<>x2 then write('khong tim thay ',x2,' trong day so tren');

end;

procedure yc5;

begin

    for i:=1 to n do

    begin

      write('nhap phan tu a[',i,']:');readln(a[i]);

    end;

    write('nhap vi tri:');readln(vt);

    for i:=1 to n do

    if (vt=i) then writeln('phan tu o vi tri ',vt,' la:',a[vt]:3);

    for i:=vt to n-1 do a[i]:=a[i+1];

    for i:=n downto vt+1 do a[i]:=a[i-1];

    write('nhap so can sua:');readln(a[vt]);

    writeln('day so sau khi sua la:');

    for i:=1 to n do write(a[i]:3); writeln;

end;

procedure yc6;

begin

  for i:=1 to n do

  begin

   write('nhap phan tu a[',i,']:');readln(a[i]);

  end;

  write('nhap vi tri can chen k:');readln(k);

  for i:=n+1 downto k+1 do a[i]:=a[i-1];

  write('nhap so can chen vao  day:');readln(a[k]);

  writeln('day so sau khi chen ',a[k],' vao  day la:');

  for i:=1 to n+1 do write(a[i]:3);writeln;

end;

procedure yc7;

begin

  for i:=1 to n do

  begin

   write('nhap phan tu a[',i,']:');readln(a[i]);

  end;

  for i:=1 to n do

  write(a[i]:3);

  writeln;

end;

BEGIN

  clrscr;

  while ch<8 do

  begin

    clrscr;

    writeln('CHON MOT TRONG CAC SO SAU:');

    writeln('1.NHAP DAY SO:');

    writeln('2.SAP XEP DAY SO:');

    writeln('3.TIM MOT SO:');

    writeln('4.XOA MOT SO:');

    writeln('5.SUA MOT SO:');

    writeln('6.CHEN MOT SO:');

    writeln('7.IN DAY SO:');

    writeln('8.THOAT KHOI CHUONG TRINH:');

    write('nhap so co yeu cau ban muon lam:');readln(ch);

    if ch<8 then

    begin write('nhap so n:');readln(n); end;

    case ch of

      1:yc1;

      2:yc2;

      3:yc3;

      4:yc4;

      5:yc5;

      6:yc6;

      7:yc7;

    end;

    readln;

  end;

  readln;

end.

uses crt;

var a:array[1..100]of real;

i,n:integer;

min,t:real;

begin

clrscr;

write('Nhap n='); readln(n);

for i:=1 to n do 

  begin

write('A[',i,']='); readln(a[i]);

end;

min:=a[1];

for i:=1 to n do 

  if min>a[i] then min:=a[i];

writeln('Gia tri nho nhat la: ',min:4:2);

t:=0;

for i:=1 to n do 

 if i mod 2=0 then t:=t+a[i];

writeln('Tong cac phan tu co chi so chan la: ',t:4:2);

readln;

end. 

uses crt;

var a:array[1..100]of integer;

i,n:integer;

begin

clrscr;

write('n='); readln(n);

for i:=1 to n do 

begin

write('A[',i,']='); readln(a[i]);

end;

readln;

end.

uses crt;

var a:array[1..100] of integer;

max,n,i:integer;

begin

writeln('nhap do dai cua day');readln(n);

for i:=1 to n do begin writeln('A[',i,']=;);readln(a[i]); end;

max:=a[1];

for i:=2 to n do if a[i] > max then begin

max:=a[i]; writeln('vi tri cua max trong day la',i);end;

 readln

end.

thật ra thì cũng không cần biến max nhưng mình làm vậy cho dễ hiểu hơn nhé!

*Thuật toán:

-Bước 1: Nhập n và nhập dãy số

-Bước 2: max←a[1]; i←1;

-Bước 3: i←i+1;

-Bước 4: Nếu max<a[i] thì max←a[i];

-Bước 5: Nếu i<=n thì quay lại bước 3

-Bước 6: Cho for chạy từ 1 đến n

Nếu a[i]=max thì xuất i

-Bước 7: Kết thúc

uses crt;

var a:array[1..100]of integer;

i,n,nn,s:integer;

begin

clrscr;

readln(n);

for i:=1 to n do readln(a[i]);

nn:=a[1];

s:=1;

for i:=1 to n do 

begin

if nn>a[i] then nn:=a[i];

s:=s*a[i];

end;

writeln(nn);

writeln(s);

readln;

end.

uses crt;

var a:array[1..100]of integer;

i,n,max,min:integer;

begin

clrscr;

write('Nhap n='); readln(n);

for i:=1 to n do 

  begin

write('A[',i,']='); readln(a[i]);

end;

max:=a[1];

min:=a[1];

for i:=1 to n do

  begin

if max<a[i] then max:=a[i];

if min>a[i] then min:=a[i];

end;

writeln('Gia tri lon nhat la: ',max);

writeln('Gia tri nho nhat la: ',min);

readln;

end.