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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.
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uses crt;
var n,i,s:integer;
begin
clrscr;
repeat
write('Nhap n='); readln(n);
until n>0;
s:=0;
for i:=1 to n do
s:=s+i;
writeln('Ket qua la: ',s);
readln;
end.
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Program bt_3;
Uses crt;
Var Tong, n, i: integer;
Begin
Clrscr;
Writeln(‘nhap n=’);
Readln (n);
Tong:=0;
For i:=1 to n do
If I mod 3 = 0 then Tong:=Tong+i;
Writeln(‘Tong la:’,Tong);
Readln
End.
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Bài 1:
function canbac2(x:longint):real;
begin
canbac2:=sqrt(x);
end;
Bài 2:
function tong(n:longint):longint;
var s,i:longint;
begin
s:=0;
for i:=1 to n do
s:=s+i;
tong:=s;
end;
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Program bt_3;
Uses crt;
Var Tong, n, i: integer;
Begin
Clrscr;
Writeln(‘nhap n=’);
Readln (n);
Tong:=0;
For i:=1 to n do
If I mod 5 = 0 then Tong:= Tong+i;
Writeln(‘Tong la:’,Tong);
Readln
End.
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Program bt_3;
Uses crt;
Var Tong, n, i: integer;
Begin
Clrscr;
Writeln(‘nhap n=’);
Readln (n);
Tong:=0;
For i:=1 to n do
If I mod 2 = 1 then Tong:= Tong+i;
Writeln(‘Tong la:’,Tong);
Readln
End.
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Program bt_3;
Uses crt;
Var Tong, n, i: integer;
Begin
Clrscr;
Writeln(‘nhap n=’);
Readln (n);
Tong:=0;
For i:=1 to n do
If I mod 2 = 0 then Tong:= Tong+i;
Writeln(‘Tong la:’,Tong);
Readln
End.
a.
var S,i,n: integer;
begin
writeln ('Nhap so nguyen duong n'); readln(n);
repeat
writeln ('nhap lai'); readln(n);
until (n>=1);
S:=0;
for i:=1 to n do S:=S+ sqr(i);
writeln ('tong la ',S);
readln;
end.
b.
var S,i,n: integer;
begin
writeln ('nhap so nguyen duong n'); readln(n);
repeat
writeln ('nhap lai'); readln(n);
until (n>=1);
S:=0;
for i:= 1 to n do
if i mod 2 = 1 then S: = S+i;
writeln ('tong la ',S);
readln;
end.
(mình không thử nên cũng chưa biết chắc đúng nhưng mong là đúng :))