C1:

khai báo:

      program  hieu_a_va_b   ("tự đặt tên cái này ko cần thiết)

      uses crt;

      var a, b : integer

phần thân:

       begin

            writeln ("nhap so a");  read(a);

            writeln ("nhap so b");  read(b);

             writeln ("hieu cua hai so la: a - b=" , a - b);

        end.

C2:

khai báo:

      program    tinh_ba_so

      uses crt;

      var a, b, c : integer

phần thân:

       begin

            writeln ("nhap so a");  read(a);

            writeln ("nhap so b");  read(b);

            writeln ("nhap so c");  read(c);

             writeln ("ket qua cua phep tinh a+b-c la" , a+b-c);

        end.

C3:

khai báo:

      program    tinh_ba_so

      uses crt;

      var x, y, z : integer

phần thân:

       begin

            writeln ("nhap so x");  read(x);

            writeln ("nhap so y");  read(y);

            writeln ("nhap so z");  read(z);

             writeln ("ket qua cua phep tinh (x+y)*z la") , (x+y)*z);

        end.

nhớ chạy thử chương trình nha. xem có lỗi ko.

(nhớ tick cho mk nha)

Câu 2: 

#include <bits/stdc++.h>

using namespace std;

long long a,b;

int main()

{

cin>>a>>b;

cout<<a-b;

return 0;

}

Câu 1: 

#include <bits/stdc++.h>

using namespace std;

double a,b,c;

int main()

{

cin>>a>>b>>c;

cout<<fixed<<setprecision(2)<<a*b*c;

return 0;

}

Câu 1: 

uses crt;

var a,s,p:real;

begin

clrscr;

repeat

write('Nhap do dai canh hinh vuong:'); readln(a);

until a>0;

p:=4*a;

s:=sqr(a);

writeln('Chu vi hinh vuong la: ',p:4:2);

writeln('Dien tich hinh vuong la: ',s);

readln;

end.

Câu 2: 

uses crt;

var a,b,t,s,h:real;

begin

clrscr;

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

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

t:=a+b;

h:=a-b;

s:=a*b;

writeln('Tong la: ',t:4:2);

writeln('Hieu la: ',h:4:2);

writeln('Tich la: ',s:4:2);

readln;

end.

Câu 3: 

uses crt;

var a,b,c:real;

begin

clrscr;

repeat

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

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

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

until (a>0) and (b>0) and (c>0);

if (a+b>c) and (a+c>b) and (b+c>a) then writeln('Day la ba canh trong mot tam giac')

else writeln('Day khong la ba canh trong mot tam giac');

readln;

end.

Câu 1: 

uses crt;

var a,b:integer;

begin

clrscr;

readln(a,b);

write(a+b);

readln;

end.

Câu 2:

uses crt;

var a,b,c:integer;

begin

clrscr;

readln(a,b,c);

writeln(a+b-c);

readln;

end.

Câu 3: 

uses crt;

var a,b:integer;

begin

clrscr;

readln(a,b);

writeln(a-b);

readln;

end.

Câu 4: 

uses crt;

var x,y,z:integer;

begin

clrscr;

readln(x,y,z);

writeln((x+y)*z);

readln;

end.

Câu 1:

Program HOC24;

var i,n: integer;

t: longint;

write('Nhap N: '); readln(n);

t:=1;

for i:=1 to n do t:=t*i;

write(n,'! = ',t);

readln

end.

Câu 2:

Program HOC24;

var i,n: integer;

S: real;

begin

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

S:=0;

for i:=1 to n do S:=S+1/i;

write('S = ',s);

readln

end.

Câu 1: 

uses crt;

var s,i:integer;

begin

clrscr;

s:=0;

for i:=1 to 10 do 

  s:=s+i;

writeln('Tong cua 10 so tu nhien dau tien la: ',s);

readln;

end.

Câu 2: 

uses crt;

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

i,n,dem: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]>0 then inc(dem);

writeln('So luong phan tu duong la: ',dem);

readln;

end.

Câu 3: 

uses crt;

var i,j:integer;

begin

clrscr;

for i:=1 to 9 do 

  begin

      writeln('Bang nhan ',i,' la: ');

for j:=1 to 10 do 

  writeln(i,'*',j,'=',i*j);

delay(200);

end;

readln;

end.

Câu 6:

uses crt;

var n,i:integer;

begin

clrscr;

readln(n);

for i:=1 to n do 

if n mod i=0 then write(i:4);

readln;

end.

5:

uses crt;

var n,i,dem:integer;

begin

clrscr;

readln(n);

dem:=0;

for i:=0 to n do

if i mod 2=1 then 

begin

write(i:4);

dem:=dem+1;

end;

writeln;

writeln(dem);

readln;

end.

Câu 1:

program Tinhtong:

var

     n, i, sum: integer;

begin

     write('Nhap n: ');

     readln(n);

     sum := 0;

     for i := 2 to n do

     begin

          if i mod 2 = 0 then

          begin

               sum := sum + i;

          end;

     end;

     writeln('Tong cac so chan tu 2 toi ', n, ' la ', sum);

     readln; 

end.

Câu 2:

program Tinhtong:

var

     n, i, sum: integer;

begin

     write('Nhap n: ');

     readln(n);

     sum := 0;

     for i := 1 to n do

     begin

          if i mod 2 = 1 then

          begin

               sum := sum + i;

          end;

     end;

     writeln('Tong cac so le tu 1 toi ', n, ' la ', sum);

     readln;

end.