The number 151 is a prime palindrome because it is both a prime number and a palindrome (it is the same number when read forward as backward). Write a program that finds all prime palindromes in the range of 3 and 1,000,000,000.

Output
The list of palindromic primes in numerical order, one per line. Then print the run time (seconds) at the last line.

Sample Output

3
5
7
11
101
131
151
181
191
313
353
373
383
...
...
30 seconds The final score

The final score Score = Style(10) + Correct(50) + Speed(T)
where T = 70 - RunTime(seconds)

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
int sushu(long x)//判断数是否是素数，若不为素数输出0，否则输出不为0的数
{
long a=1;
int c=1;
double k;k=sqrt(x);
while(c&&a<k+1)
{
a++;c=x%a;
}
return c;
}
int nixushu(long x)//求一个数的逆序数
{
int a;
long b=0;

while(x)
{
a=x%10;x=x/10;b=b*10+a;
}
return b;
}

int main()
{
long a;
double D=pow(10,8);
for(a=3;a<10*D;a+=2)
{
if(a<2*D||(a>3*D&&a<4*D)||(a>7*D&&a<=8*D)||a>=9*D)//数a开头为24568的不计入
{
if(nixushu(a)==a)
{
if(sushu(a))
{
printf("%ld\n",a);
}
}
}
}

printf("------END----________--------");
return 0;

}
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