typedef struct Operator
{
	char symbol;
	int operands;
	union
	{
		void *f;
		double (*f0)(void);
		double (*f1) (double x);
		double (*f2) (double x, double y);
	}
}Operator;

Operator mult={'*',2,multiply1};
Operator add={'+',2,add1};
Operator neg={'-',1,neg1};
Operator divide={'/',2,divide1};
Operator square={'sq',1,square1};
Operator sqrt={'sqrt',1,squareRoot1};
Operator min={'m',2,min1};
Operator max={'M',2,max1};
Operator expo={'^',2,expo1};
Operator pi={'pi',0,pi};
Operator loga={'log',1,L};
Operator expon={'e^',1,E};

double main (void)
{
	Operator op[12]={mult, add, neg};
}