Câu 1:

var i,n:integer;

s:longint;

begin

Write('n = ');readln(n)

for i:=1 to n do

s:=s+2*i+1;

write('tong la: ',s);

readln

end.

Câu 2

Bài 5:

Var b:array:[1..1000] of integer;

i,n,max:integer;

Begin

Write('n = ');readln(n);

For i:=1 to n do

Begin

Write('Nhap so thu ',i,' = ');readln(b[i]);

End;

Write('Cac phan tu am la: ');

For i:=1 to n dko

if b[i]<0 then write(b[i]:8);

writeln;

max:=b[1];

For i:=2 to n do

If b[i] > max then max:=b[i];

write('So lon nhat la ',max);

Readln

End.

Cau 1:

Câu 2:

#include <bits/stdc++.h>

using namespace std;

long long n;

int main()

{

cin>>n;

if (n>0 && n%5==0) cout<<"Phai";

else cout<<"Khong phai";

}

int main() 

{

int n;

long s;

s=0;

i=1;

printf("\nSo n la: ");

scanf("%d",&n);

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

    {

    s=s+i;

    }

printf("\nTổng %d là %ld: ", n, s);

}

program Le_Nho_Hon_Hoac_Bang_n;

uses crt;

var

       n, i: integer;

begin

       clrscr;

       write('Nhap vao mot so nguyen duong n: ');

       readln(n);

       while n <= 0 do

       begin

              writeln('So ban nhap khong hop le. Xin vui long nhap lai: ');

              readln(n);

       end;

       clrscr;

       writeln('Cac so le nho hon hoac bang ', n, ' la:');

       i := 1;

       while i <= n do

       begin

              if i mod 2 <> 0 then

                     writeln(i);

              i := i + 1;

       end;

       readln;

end.

1:

uses crt;

var n,i,t:integer;

begin

clrscr;

readln(n);

t:=0;

for i:=1 to n do

t:=t+i*i;

write(t);

readln;

end.

2

program bt2;

var i,n,t:integer;

begin

readln(n);

s:=0;

for i:=1 to n do

if i mod 2 = 1 then s:=s+i;

readln;

end.

Câu 1:

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

Câu 2: 

uses crt;

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

i:integer;

begin

clrscr;

for i:=1 to 10 do 

  begin

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

end;

for i:=1 to 10 do 

 write(a[i]:4);

readln;

end.

Câu 3: 

uses crt;

var a:array[1..15]of integer;

i,n,t:integer;

begin

clrscr;

repeat

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

until (0<n) and (n<=15);

for i:=1 to n do 

begin

repeat

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

until a[i]<=100;

end;

writeln('Mang da nhap la: ');

for i:=1 to n do 

  write(a[i]:4);

writeln;

t:=0;

for i:=1 to n do

if a[i] mod 3=0 then t:=t+a[i];

writeln('Tong cac phan tu chia het cho 3 la: ',t);

writeln('Cac so chan o vi tri le trong day la: ');

for i:=1 to n do 

  if (a[i] mod 2=0) and (i mod 2=1) then write(a[i]:4);

readln;

end.

Program HOC24;

var n,i: integer;

s: longint;

begin

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

s:=2021;

for i:=0 to n do s=s+(2*i+1);

write('S= ',s);

readln

end.

*Cách 2: Dùng While do

uses crt;

var s,i,n:integer;

begin

clrscr;

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

s:=2021;

i:=0;

while i<=n do 

  begin

s:=s+(2*i+1);

i:=i+1;

end;

writeln(s);

readln;

end.