// Flawed examples of defining and using a struct

#define NAMELENGTH 20
#include <stdio.h>
#include <stdlib.h>

// void read(struct customer c);	// ERROR - data type not yet declared

int main(void)
{				// definition can only be used in main
	struct customer {		// both words are the data type
		char name[NAMELENGTH];
		float acctbal;
	} c1, *cptr;			// variables of the new type

	struct customer carray[5];	// array of the new type

//	c1.name = "Jill";	// ERROR - incompatible types
	c1.acctbal = 10000;
//	puts(c1);		// ERROR - c1 is not a string
	cptr = carray+4;	// make sure it points to something!
//	*cptr.acctbal = 1000;	// compiler ERROR - binds incorrectly
	(*cptr).acctbal = 100;	// works
	cptr->acctbal = 1000;	// better
	carray[0].acctbal = 100;
//	read(carray[1]);
	puts(carray[1].name);
}

/*
void read(struct customer c)	// ERROR - passed by value
{				// function wouldn't affect param in main
	char balance[20];
	printf("enter name: ");
	gets(c.name);
	printf("enter account balance: $");
	gets(balance);
	c.acctbal = atof(balance);
}
*/