uses crt;

var n,i,o,d:integer;

function ktnt(n:integer): integer;

var i,d:integer;

begin

d:=0;

for i:=1 to sqrt(n) do

if (n mod i=0) then d:=d+1;

if d=2 then ktnt=0

else ktnt=1;

end;

begin

readln(n);

writeln(' so nguyen to be hon hoac bang n la'); {a}

for i:=1 to n do

if ktnt(i)=0 then writeln(i);

writeln('so nguyen to nho nhat khong be hon n');

o:=n;

while o>0 do

begin

if ktnt(o)=0 then

begin

write(o);

break;

end;

o:=o+1;

end;

writeln('cặp số nguyên tố là hai số nguyên lẻ liên tiếp nhỏ hơn hoặc bằng n');

o:=0;

o:=1;

d:=0;

for i:=o+2 to n do

begin

if ktnt(i)=0 then

begin

d:=d+1;

write(i,' ');

if d<2 then continue;

end;

d:=0;

writeln;

end;

readln;

end.

uses crt;var n: longint;    chrn: string;    valn,sum,max,i,preperror: byte;begin    write('Nhap so can kiem tra: ');    readln(n);    str(n,chrn);    for i:=1 to length(chrn) do    begin        val(chrn[i],valn,preperror);        sum:=sum+valn;        if max<valn then max:=valn;        valn:=0    end;    writeln('Ket qua: ');    writeln(length(chrn));    writeln(sum);    write(max);    readln;end.uses crt;var n: longint;    chrn: string;    valn,sum,max,i,preperror: byte;begin    write('Nhap so can kiem tra: ');    readln(n);    str(n,chrn);    for i:=1 to length(chrn) do    begin        val(chrn[i],valn,preperror);        sum:=sum+valn;        if max<valn then max:=valn;        valn:=0    end;    writeln('Ket qua: ');    writeln(length(chrn));    writeln(sum);    write(max);    readln;end.

Program HOC24;

var N:longint;

max,tg,t,d: integer;

Begin

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

max:=0;

while n<>0 do

begin

tg:=n mod 10;

d:=d+1;

t:=t+tg;

if tg>max then max:=tg;

n:=n div 10;

end;

writeln('So nguyen N co ',d,' chu so');

writeln('Tong cac chu so cua N la : ',t);

write('Chu so lon nhat cua N la :',max);

readln

end.

uses crt;

var n,d,i,t,max,x:longint;

y:integer;

st:string;

begin

clrscr;

repeat

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

until n>0;

str(n,st);

d:=length(st);

writeln('So chu so cua ',n,' la: ',d);

t:=0;

max:=0;

for i:=1 to d do 

  begin

val(st[i],x,y);

t:=t+x;

if max<x then max:=x;

end;

writeln('Tong cac chu so cua ',n,' la: ',t);

writeln('Chu so lon nhat cua ',n,' la: ',max);

readln;

end.

câu 1

Program Nguyen_to;

Var n,i:integer;

Function NT(n:integer):Boolean;

Var ok: Boolean;

i: integer;

Begin ok:=true;

for i:=2 to n-1 do if (n mod i)= 0 then ok:=ok and false;

if n < 2 then NT:=false else NT:=ok;

End;

Begin Write('Nhap n: ');

Readln(n); i:=n;

Repeat i:=i+1;

Until NT(i);

Write('So nguyen to nho nhat lon hon ',n, 'la: ',i);

Readln End.

câu 2

uses crt;

const so: set of char=['0','1','2','3','4','5','6','7','8','9'];

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

st,b:string;

c,l,i,n,j:integer;

s, Max: integer;

begin clrscr;

write('Nhap xau:');

readln(st);

l:=length(st);

i:=1;

n:=0;

repeat if (st[i] in so) then begin b:=''

repeat b:=b+st[i];

inc(i);

until (not(st[i] in so)) or (i>l);

inc(n);

val(b,a[n],c);

end;

inc(i);

until i>l;

Max:=a[1];

for i:=2 to n do If Max<A[i] Then Max:=A[i];

Writeln('Phan tu lon nhat cua mang:', Max);

readln;

end.

program so_nguyen_to;

uses crt;

var i,n:integer;

function kt(n:integer):boolean;

var i,j:integer;

begin

j:=0;

for i:=1 to n do

if n mod i=0 then inc(j);

if j=2 then kt:=true

else kt:=false;

end;

BEGIN

clrscr;

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

if kt(n) then writeln(n,' la so nguyen to')

else writeln(n,' khong phai la so nguyen to');

writeln('cac so nguyen to be hon hoac bang ',n,' la:');

for i:=1 to n do

if kt(i) then write(i:5);

writeln;

writeln('cac cap so le lien tiep la so nguyen to be hon hoac bang ',n,' la:');

for i:=1 to n do

if (i mod 2=1) and (kt(i)) and (kt(i+2)) then write(i,',',i+2);

readln;

end.

câu c bạn viết cách ra nhé!

#include <stdio.h>

int main(){

    int n;

    scanf("%d",&n);

    long t=0; int i,j;

    for (i=2; i<=n; i++){

        int c=0;

        for (j=2; j<i; j++)

            if (i%j==0) c++;

        if (c==0) t=t+i;

        }

printf("%d",t);

return 0;

}

Bạn trình bày lại đề bài rõ hơn nha, đề đọc rất khó hiểu ấy.

uses crt;

var n,i,dem,j,t:integer;

kt:boolean;

begin

clrscr;

readln(n);

t:=0;

for i:=2 to n do 

begin

kt:=true;

for j:=2 to i-1 do 

  if i mod j=0 then kt:=false;

if kt=true then 

begin

write(i:4);

t:=t+i;

end;

end;

writeln;

writeln(t);

readln;

end.

uses crt;

var a:array[1..20]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;

for i:=1 to n do 

  write(a[i]:4);

writeln;

t:=0;

for i:=1 to n do 

 t:=t+a[i];

writeln('Tong cua day la: ',t);

for i:=1 to n do 

 if a[i]>50 then write(a[i]:4);

writeln;

for i:=1 to n do 

 if a[i]<30 then write(a[i]:4);

readln;

end.

1:

uses crt;

var t,x,i,n:integer;

begin

clrscr;

t:=0;

n:=10;

for i:=1 to n do

begin

readln(x);

t:=t+x;

end;

write(t);

readln;

end.

2: 

uses crt;

var dem,x,i,n:integer;

begin

clrscr;

dem:=0;

n:=10;

for i:=1 to n do

begin

readln(x);

if x mod 2=0 then inc(dem);

end;

write(dem);

readln;

end.

3

program Cacsole;
uses crt;
var M, N, i: integer;
begin
clrscr;
write ('Nhap M= '); readln(M);
write ('Nhap N= '); readln(N);
for i := M to N do

if  i mod 2 = 1 then
write (i,' ');
readln;
end.