Wrong CPP solution

BANROB1.cpp

#include<bits/stdc++.h>
using namespace std;
 
main()
{
    #ifndef ONLINE_JUDGE
        freopen("input.txt", "r", stdin);
        //freopen("output.txt","w",stdout);
    #endif
    long long  t;
    scanf("%lld",&t);
 
    while(t--)
    {
        long long  m;
        long double mon = 1000000000;
        long double p;
        scanf("%lld%Lf",&m,&p);
 
        if(!p)
        {
            if(m%2==1)
                printf("1000000000.000000 0.000000\n");
            else
                printf("0.000000 1000000000.000000\n");
 
            continue;
        }
 
        long double fir;
 
        if(m%2==1)
            fir=mon*(1+pow(p,m));
        else 
            fir=mon*(1-pow(p,m));
        
 
        fir/=(1+p);
        printf("%Lf %Lf\n",fir,mon-fir);
 
    }
	return 0;
}