#include<stdio.h>

#include<conio.h>

#include<math.h>

#include<stdlib.h>

#include<string.h>

int nguyento(long n)

{

for(long i=2;i<=sqrt(n);i++)

if(n%i==0) return 0;

return 1;

}

int thuannghich10(long n)

{

char *s1,*s2;

ltoa(n,s1,10);

strcpy(s2,s1); //sau dau la dich sau sau la nguon

strrev(s1); //nho lat nguoc sau

if(strcmp(s1,s2)==0)

return 1;

return 0;

}

int thuannghich16(long n)

{

char *s1,*s2;

ltoa(n,s1,16);

strcpy(s2,s1);

strrev(s1);

if(strcmpi(s1,s2)==0)

return 1;

return 0;

}

void main()

{

long i=1234;

for(i=1000000;i<=9999999;i++)

if(nguyento(i)) printf("

%ld",i);

getch();clrscr();

for(i=1000000;i<=9999999;i++)

if( thuannghich10(i))

printf("%10ld",i);

getch();clrscr();

for(i=1000000;i<=9999999;i++)

if( thuannghich10(i) && thuannghich16(i))

printf("%10ld",i);

getch();

}