Question

Hi, I need to make a program in C that reads the type of currency and organizes them into stacks based on currency which can be read back. This is what I have so far, can I get help finishing it?

#include <stdio.h>
#include <stdlib.h>
const float POUND = 1.31;
const float YEN = 0.0091;
const float RUPEE = 0.014;
const float EURO = 1.11;
char c;
int currValue;
float exchangeValue;
float finValue;
int printValue;

struct node {
   int value;
   struct node *next;
};

struct node *dollarHead;
struct node *poundHead;
struct node *euroHead;
struct node *yenHead;
struct node *rupeeHead;
struct node *head;
int main(){
   dollarHead = malloc(sizeof(struct node));
   poundHead = malloc(sizeof(struct node));
   euroHead = malloc(sizeof(struct node));
   yenHead = malloc(sizeof(struct node));
   rupeeHead = malloc(sizeof(struct node));
   head = malloc(sizeof(struct node));

   if (head == NULL){
   printf("UHHH ERROR");
} else {
   printf("%x\n", head);
head->value = 36;
head->next = NULL;
printf("h value: %x\n", head->value);
printf("h next: %x\n", head->next);

float currencyExchange() {
   float exchangeRate = 1;
   c = getchar();
   if ( c == '$') {
       printf("$");
       return exchangeRate;
} else if (c =='\xC2') {
   c = getchar();
if (c == '\xA3') {
   printf("£");
   exchangeRate = POUND;
   return exchangeRate;

} else if (c == '\xA5') {
   printf("Â¥");
   exchangeRate= YEN;
   //printf("the exchange rate is %f",exchangeRate);
   return exchangeRate;
   }
   else{
   c = getchar();
   c = getchar();
   if(c== '\xB9') {
   printf("₹");
   exchangeRate = RUPEE;
   return exchangeRate;
   }
   else if (c == '\xAC') {
   printf("€");
   exchangeRate = EURO;
   return exchangeRate;
   }
   else
                   }
                   }
               }
   //

Answer 1

This problem can be solved by using a double pointer of type node.So that it can hold the currency type pointer and it updates the corresponding pointer.As C doesnot have reference (C supports only pointers where as C++ supports boyh pointers and references),double pointer plays a key role and it can be solved.

struct node** head;

#include <stdio.h>
#include <stdlib.h>
const float POUND = 1.31;
const float YEN = 0.0091;
const float RUPEE = 0.014;
const float EURO = 1.11;
char c;
int currValue;
float exchangeValue;
float finValue;
int printValue;

struct node{
int value;
struct node* next;
};
struct node *dollarHead=NULL;
struct node *poundHead=NULL;
struct node *euroHead=NULL;
struct node *yenHead=NULL;
struct node *rupeeHead=NULL;
struct node *head=NULL;
void insert(float value){
struct node** head;
if(value==POUND)
{
head=&poundHead;
}
else if(value==YEN)
{
head=&yenHead;
}
else if(value==RUPEE)
{
head=&rupeeHead;
}
else if(value==1)
{
head=&dollarHead;
}
else if(value==EURO)
{
head=&euroHead;
}
struct node* temp=(node*) malloc(sizeof(struct node));
printf("Enter value");
scanf("%d",&temp->value);
temp->next=NULL;
if(*head==NULL)
{
*head=temp;
}
else
{
temp->next=*head;
*head=temp;
}
}
void print(float value )
{
struct node** head;
if(value==POUND)
{
head=&poundHead;
}
else if(value==YEN)
{
head=&yenHead;
}
else if(value==RUPEE)
{
head=&rupeeHead
}
else if(value==1)
{
head=&dollarHead
}
else if(value==EURO)
{
head=&euroHead;
}
struct node* temp=*head;
while(temp!=NULL)
{
printf("%d ",temp->value);
temp=temp->next;
}
printf("\n");
}
int main(){
while(1)
{
float rate=currencyExchange();
if(rate==POUND)
{
insertpound(rate);
}
else if(rate==YEN)
{
insert(rate);
}
else if(rate==RUPEE)
{
insert(rate);
}
else if(rate==1)
{
insert(rate);
}
else if(rate==EURO)
{
insert(rate);
}
printf("Do you want to continue...if yes press Y else N");
char s;
scanf("%c",&s);
if(s=='Y' || s=='y')
continue;
else
break;
}
printf("Pound currency ");
print(POUND);
printf("Yen currency ");
print(YEN);
printf("Rupee currency ");
print(RUPEE);
printf("Euro currency ");
print(EURO);
printf("Dollar currency ");
print(1);
}
float exchangeValue(){
    float exchangerate=1;
    c = getchar();
    if ( c == '$') {
       printf("$");
       return exchangeRate;
}
else if (c =='\xC2') {
    c = getchar();
if (c == '\xA3') {
    printf("£");
    exchangeRate = POUND;
    return exchangeRate;
}
else if (c == '\xA5') {
    printf("Â¥");
    exchangeRate= YEN;
   //printf("the exchange rate is %f",exchangeRate);
    return exchangeRate;
    }
   else{
    c = getchar();
    c = getchar();
    if(c== '\xB9') {
    printf("₹");
    exchangeRate = RUPEE;
    return exchangeRate;
   }
   else if (c == '\xAC') {
    printf("€");
    exchangeRate = EURO;
    return exchangeRate;
   }
  
  }
}
}