UVa problem solution 12802 - Gift From the Gods

problem link:

Discuss: In this problem it is common mistake to the integer after double to check weather it is palindrome or prime but the original integer have to checked. and one thing in this problem not describe that less then 2 will be consider as prime.next just check palindrome and prime it'll be okay.


try your self  before see the code




#include<bits/stdc++.h>
using namespace std;
int palin(long long n)
{
    long long m,rev;
    m=n;
    rev=0;
    while(n>0)
    {
        int dig=n%10;
        rev=rev*10+dig;
        n/=10;
    }
    if(rev==m)
        return true;
    return false;
}
int prime(long long n)
{
    int i,flag=0;

    if(n<2)
        return false;
    else
    for(i=2;i<=sqrt(n);i++)
    {
        if(n%i==0)
            flag=1;
    }
    if(flag)
        return true;
    return false;
}
int main()
{
   // freopen("input.txt","r",stdin);
   // freopen("out.txt","w",stdout);
    long long n,i,j,d,t;
    while(cin >>n)
    {
        t=n*2;
        cout <<t<<endl;
       if(!prime(n)&&palin(n))
        break;
    }
    return 0;
}