package fengshiji;
import  java.math.*;
public class fengshiji1 
{
	public double duishu(double a,double b)
	{
		double res = log(a, b);
	return res;
	}

	private double log(double a, double b) {
		double h=Math.log10(b)/Math.log10(a);
		return h;
	}

}