Câu 1: 

uses crt;

const fi='nguon.txt'

var f1:text;

a,b,c:integer;

begin

clrscr;

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

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

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

assign(f1,fi); rewrite(f1);

writeln(f1,a);

writeln(f1,b);

writeln(f1,c);

close(f1);

readln;

end.

Câu 2: 

const fi='nguon.txt'

fo='kq.txt'

var f1,f2:text;

a,b,c,max,min:integer;

begin

assign(f1,fi); reset(f1);

assign(f2,fo); rewrite(f2);

readln(f1,a);

readln(f1,b);

readln(f1,c);

writeln(f2,(a+b+c)/3:4:2);

max:=a;

if max<b then max:=b;

if max<c then max:=c;

writeln(f2,max);

min:=a;

if min>b then min:=b;

if min>c then min:=c;

writeln(f2,min);

close(f1);

close(f2);

end.

#include <bits/stdc++.h>

using namespace std;

long long a[10],b[10],i,j;

int main()

{

freopen("input.txt","r",stdin);

freopen("output.txt","w",stdout);

for (i=1; i<=10; i++) cin>>a[i];

for (j=1; j<=10; j++) cin>>b[j];

for (i=1; i<=10; i++)

cout<<a[i]+b[i]<<" ";

return 0;

}

help

const fi='input.txt'

fo='output.txt'

var f1,f2:text;

a,b,c,max:real;

begin

assign(f1,fi); reset(f1);

assign(f2,fo); rewrite(f2);

readln(f1,a,b,c);

min:=a;

if min>b then min:=b;

if min>c then min:=c;

writeln(f2,min);

close(f1);

close(f2);

end.

#include <bits/stdc++.h>

using namespace std;

long long a,b,c,d;

int main()

{

freopen("input.txt","r",stdin);

freopen("output.txt","w",stdout);

cin>>a>>b>>c>>d;

cout<<a+b+c+d;

return 0;

}

uses crt;
const fi='input.txt';
fo='output.txt';
var f1,f2:text;
a:array[1..100]of integer;
dem,i,t:integer;
begin
clrscr;
assign(f1,fi); reset(f1);
assign(f2,fo); rewrite(f2);
dem:=0;
while not eoln(f1) do
begin
inc(dem);
read(f1,a[dem]);
end;
writeln(f2,'so luong so nguyen co trong day la: ',dem);
{---------------tinh-tong------------------}
t:=0;
for i:=1 to dem do
t:=t+a[i];
writeln(f2,'tong gia tri cac so nguyen trong day la: ',t);
close(f1);
close(f2);
readln;
end.

program TimMinMaxTrungBinh;

var

      N, i, max, min, sum: integer;

      a: array[1..50] of integer;

      TB, minTB, maxTB: real;

begin

      writeln('Nhap so nguyen duong N:');

      readln(N);

      sum := 0;

      for i := 1 to N do

      begin

            write('Nhap so thu ', i, ': ');

            readln(a[i]);

            sum := sum + a[i];

      end;

      max := a[1];

      min := a[1];

      for i := 2 to N do

      begin

            if a[i] > max then

                  max := a[i];

            if a[i] < min then

                  min := a[i];

      end;

      TB := sum / N;

      minTB := TB;

      maxTB := TB;

      for i := 1 to N do

      begin

            if (a[i] < TB) and (a[i] < minTB) then

                  minTB := a[i];

            if (a[i] > TB) and (a[i] > maxTB) then

                  maxTB := a[i];

      end;

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

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

      writeln('Gia tri trung binh la: ', TB:2:2);

      if minTB = TB then

            writeln('Khong co gia tri nao nho hon TB')

      else

            writeln('Gia tri nho nhat < TB la: ', minTB);

      if maxTB = TB then

            writeln('Khong co gia tri nao lon hon TB')

      else

            writeln('Gia tri lon nhat > TB la: ', maxTB);

      readln;

end.