Câu 1: 

uses crt;

var a:array[1..500]of integer;

i,n,t:integer;

begin

clrscr;

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

for i:=1 to n do 

  begin

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

  end;

t:=0;

for i:=1 to n do 

  if (a[i]<0) and (a[i] mod 7=0) then t:=t+a[i];

writeln('Tong cac so am chia het cho 7 la: ',t);

readln;

end.

Câu 2: 

uses crt;

var c,a:array[1..10]of integer;

i,kt,j,dem:integer;

begin

clrscr;

for i:=1 to 10 do 

  begin

write('C[',i,']='); readln(c[i]);

end;

dem:=0;

for i:=1 to 10 do 

  if c[i]>1 then 

begin

kt:=0;

for j:=2 to c[i]-1 do 

  if c[i] mod j=0 then kt:=1;

if kt=0 then 

begin

inc(dem);

a[dem]:=c[i];

end;

end;

if dem=0 then writeln('Trong day khong co so nguyen to')

else begin

writeln('Cac so nguyen to trong day la: ');

for i:=1 to dem do

write(a[i]:4);

end;

readln;

end.

Câu 3: 

uses crt;

var d:array[1..200]of integer;

i,k,dem:integer;

begin

clrscr;

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

for i:=1 to k do 

  begin

write('D[',i,']='); readln(d[i]);

end;

dem:=0;

for i:=1 to k do 

  if (a[i] mod 2=0) and (a[i]>=10) then inc(dem);

writeln('So phan tu chan co 2 chu so la: ',dem);

readln;

end.

#include <bits/stdc++.h>

using namespace std;

long long n,i,x;

int main()

{

cin>>n;

long long t=0;

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

{

cin>>x;

if (x%3==0) t=t+x;

}

cout<<t;

return 0;

}

#include <bits/stdc++.h>

using namespace std;

long long a[100],n,i,t,t1,dem,dem1;

//chuongtrinhcon

bool ktnt(long long x)

{

if (x<=1) return(false);

for (int i=2; i*i<=x; i++)

if (x%i==0) return(false);

return true;

}

//chuongtrinhchinh

int main()

{

cin>>n;

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

{

cin>>a[i];

}

for (i=1; i<=n; i++) cout<<a[i]<<" ";

cout<<endl;

t=0;

for (i=1; i<=n; i++) if (a[i]%2==0) t=t+a[i];

cout<<t<<endl;

dem=0;

for (i=1; i<=n; i++) if (a[i]%3==0) dem++;

cout<<dem<<" ";

t1=0;

dem1=0;

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

if (a[i]%2!=0)

{

t1+=a[i];

dem1++;

}

cout<<fixed<<setprecision(2)<<(t1*1.0)/(dem1*1.0)<<endl;

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

if (ktnt(a[i])==true) cout<<a[i]<<" ";

return 0;

}

uses crt;

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

i,n,dem,t,tb:integer;

begin

clrscr;

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

for i:=1 to n do 

  begin

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

end;

dem:=0;

t:=0;

for i:=1 to n do 

  if a[i]>0 then

begin

dem:=dem+1;

t:=t+a[i];

end;

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

writeln('Tong cac phan tu duong la: ',t);

writeln('Trung binh cac phan tu duong la: ',t/dem:4:2);

readln;

end.

#include <bits/stdc++.h>

using namespace std;

int n,A[100],i,k,t;

int main()

{

cin>>n>>k;

for (int i=1; i<=n; i++) cin>>A[i];

t=0;

for (int i=1; i<=n; i++)

if (A[i]%k==0) t+=A[i];

cout<<t;

}

bprogram min 

uses crt 

var A: array [1...250] of integer

tong :integer;

begin 

tong:=0

writeln(‘nhap n:’); readln (n) 

forr i:=1 to n do 

begin 

writeln (‘nhap phan tu thu ‘,i);

readln (A[i] );

end

for i:=1 to n do 

begin

if (A[i] mod 3=0) 

then tong:=tong +A[i];

end

writeln (Tong cac phan tu chia het cho 3) 

readln ;

end

Program Vidu;
Uses crt;
Type Mang1C = array[1..250] of Integer; 
Var A:Mang1C;
i:integer;
Begin
        clrscr;
        Writeln
        For i:=1 to 250 do 
        Begin
                Write
                Readln
        End;
        Write
        For i:=1 to 250 do
                Write
        Readln;
End.

#include <bits/stdc++.h>

using namespace std;

long long a[10000],n,i,t;

int main()

{

cin>>n;

t=0;

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

{

cin>>a[i];

t=t+a[i];

}

for (i=1; i<=n; i++) cout<<a[i]<<" ";

cout<<endl;

dem=0;

for (i=1; i<=n; i++) 

if (a[i] %2==0) dem++;

cout<<dem<<endl;

cout<<t;

return 0;

}

#include <bits/stdc++.h>

using namespace std;

double x,t;

long long n,i;

int main()

{

cin>>n;

t=0;

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

{

cin>>x;

t+=x;

}

cout<<t;

return 0;

}