#include <iostream>
#include <math.h>
#include <stdlib.h>
using namespace std;

int main()
{
    long double a,b,l;
    cout<<"Welcome to logarithm Program\n\n";
    cout<<"\n\n*************************input first as 1 to exit**********";
    cout<<"*********************\n\n";
    while(1) {
    cout<<"input two numbers to calculate \n";
    cout<<"log of second on base of first :: ";
    cin>>a>>b;
    if(a==1 || a<0 || b<0) exit(0);
    l=(log10(b)/log10(a));
    cout<<"\nLog"<<a<<" "<<b<<" = "<<l;
    cout<<"\n\n*************************input firs as 1 to exit**********";
    cout<<"*********************\n\n";
}
    return 0;
}