Solution for Exercise 20-12

ex2012

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define ITEMS 5

struct stk {
    char symbol[5];
    int quantity;
    float price;
    struct stk *next;
};

struct stk *make_structure(void);
void fill_structure(struct stk *a,int c);
void show_structure(struct stk *a);

int main()
{
    struct stk *first;
    struct stk *current;
    int x;

    /* create the ITEMS-sized linked list */
    for(x=0;x<ITEMS;x++)
    {
        if(x==0)
        {
            first=make_structure();
            current=first;
        }
        else
        {
            current->next=make_structure();
            current=current->next;
        }
        fill_structure(current,x+1);
    }
    /* cap the list */
    current->next=NULL;

    /* output the database */
    puts("Investment Portfolio");
    printf("Symbol\tShares\tPrice\tValue\n");
    current = first;
    while(current)
    {
        show_structure(current);
        current=current->next;
    }

    return(0);
}

/* allocate a new structure */
struct stk *make_structure(void)
{
    struct stk *a;

    a=(struct stk *)malloc(sizeof(struct stk)*1);
    if(a==NULL)
    {
        puts("Some kind of malloc() error");
        exit(1);
    }

    return(a);
}

/* fill the structure with data */
void fill_structure(struct stk *a,int c)
{
    printf("Item #%d/%d:\n",c,ITEMS);
    printf("Stock Symbol: ");
    scanf("%s",a->symbol);
    printf("Number of shares: ");
    scanf("%d",&a->quantity);
    printf("Share price: ");
    scanf("%f",&a->price);
}

/* output the structure */
void show_structure(struct stk *a)
{
    printf("%-6s\t%5d\t%.2f\t%.2f\n",\
            a->symbol,
            a->quantity,
            a->price,
            a->quantity*a->price);
}

Output

Item #1/5:
Stock Symbol: IBM
Number of shares: 50
Share price: 116.98
Item #2/5:
Stock Symbol: MSFT
Number of shares: 25
Share price: 183.16
Item #3/5:
Stock Symbol: TWTR
Number of shares: 250
Share price: 29.0
Item #4/5:
Stock Symbol: QCOM
Number of shares: 67
Share price: 75.77
Item #5/5:
Stock Symbol: CSCO
Number of shares: 50
Share price: 44.27
Investment Portfolio
Symbol  Shares  Price   Value
IBM        50   116.98  5849.00
MSFT       25   183.16  4579.00
TWTR      250   29.00   7250.00
QCOM       67   75.77   5076.59
CSCO       50   44.27   2213.50

Exercise ex2013 →