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| #include <bits/stdc++.h>
using namespace std;
bool isPalindrome(int x)
{
int arr[11], idx = 0;
do
{
arr[idx++] = x % 10;
x /= 10;
} while (x);
for (int i = 0, j = idx - 1; i < j; ++i, --j)
if (arr[i] != arr[j])
return false;
return true;
}
bool isPrime(int x)
{
for (int i = 2; i <= sqrt(x); ++i)
{
if (x % i == 0)
return false;
}
return true;
}
int main()
{
int a, b;
cin >> a >> b;
if (b > 9999999)
b = 9999999;
for (int i = (a % 2 ? a : a + 1); i <= b; i += 2)
{
if (isPalindrome(i) && isPrime(i))
cout << i << endl;
}
return 0;
}
|