func_code_string: #include <bits/stdc++.h>   int prime[20000000 + 1] = {0};   int palin[20000000 + 1] = {0};   bool check[20000000 + 1] = {1, 1, 0};   void primecheck() {     for (int i = 2; i <= 20000000; i++) {       if (check[i]) {         prime[i] = prime[i - 1];         continue;       }       prime[i] = prime[i - 1] + 1;       for (int j = 2; j * i <= 20000000; j++) check[j * i] = true;     }   }   void palincheck() {     for (int i = 1; i <= 20000000; i++) {       int j = i;       int counter = 0;       while (j > 0) {         counter = counter * 10 + j % 10;         j = j / 10;       }       if (i == counter)         palin[i] = palin[i - 1] + 1;       else         palin[i] = palin[i - 1];     }   }   int main() {     primecheck();     palincheck();     int p, q;     int left, right, mid;     left = 1, right = 20000000;     mid = (left + right) / 2;     scanf( %d %d , &p, &q);     for (int i = 20000000; i >= 1; i--)       if ((long long int)q * prime[i] <= (long long int)p * palin[i]) {         printf( %d n , i);         return 0;       }     return 0;   }   