pp49bhktg/Desktop/b.hpp

#ifdef _B_HPP
void logax(double a, double x);
#endif // _B_HPP
#include<iostream>
void logax(double a, double x) {
	if (a == 0 || a == 1)
		printf("底数为0或1，非法运算\n");
	else if (x <= 0)
		printf("真数小于等于0，非法运算\n");
	else {
		double res = log(x) / log(a);
		printf("底数为%lf，真数为%lf的对数值为%.6lf\n", a, x, res);
	}
}