palindromics primes TopCoder

#include<iostream>
#include<cmath>
#include<cstring>
#include<algorithm>
#include<cstdio>
using namespace std;
class PrimePalindromic {
 public:
  string str(int n) {
   char arr[10];
   sprintf(arr, "%d", n);
   return arr;
  }
  bool pal(string s) {
   int len = s.size();
   for (int i = 0; i < len / 2; i++)
    if(s[i] != s[len - i - 1]) return false;
   return true;
  }
  int count(int A, int B) {
   int T[20];
   int res = 0;
   for (int k = A; k <= B; k++) {
    int num = k, j = 0;
    for (int i = 2; i <= sqrt(num); i++)
     while(num % i == 0) num /= i, T[j++] = i;
    if(num > 1) T[j++] = num;
    bool find = false;
    do {
     string s = "";
     for (int i = 0; i < j; i++)
      s += str(T[i]);
     if(pal(s)) find = true;
    } while(next_permutation(T, T + j) && !find);
    if(find) res++;
   }
   return res;
  }
};
int main() {
 int a, b;
 while(cin >> a >> b) {
  cout << PrimePalindromic().count(a, b) << endl;
 }
 return 0;
}