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Program for Largest Prime Palindrome (1 - 1000)



/* Program to print largest prime palindrome with range (1-1000)
    Problem - https://www.codeeval.com/open_challenges/3/
*/

#include <iostream>
using namespace std;

int main() {
        int num,i,j,digit = 0,rev = 0;
        int flag = 0;

        for (i = 1000;i >= 2;i--) {
                flag = 0,rev = 0;
                //check for prime
                for ( j =2; j < i /2;j++) {
                        if ( i % j == 0) {
                                flag = 1;break;
                }
        }

        if (!flag) {
                //if prime check for palindrome
                num = i,rev = 0;
                while (num > 0) {
                        digit = num % 10;
                        rev = rev * 10 + digit;
                        num /= 10;
                }
        }
        if ( i == rev) {
                cout << "Largest Prime Palindrome between (1-1000) = " << i << endl;
                break;
                }
        }

         return 0;
}

Output -

Largest Prime Palindrome between (1-1000) = 929
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