I got the equations to get inserted into the linked list. Now I will work on making the code easier to read. I was initially thinking of making the doubly linked list because input members in the stack would be inserted in reverse order. But I ended up making another stack(making stacks were a little more simple than making a queue although a bit more inefficient) which copied in the data from the first stack. Now when I print what I enter, it is in the correct order. Here is my current working code, I will modify it in due time.
Here is the code:
Code:
#include <iostream>
using namespace std;
struct node
{
float num;
char opr;
char type;
node* next;
node* prev;
};
void printList(const node*);
//entry* insert(int n, node* h);
//entry* deleteNode(int n, node* h);
//entry* PQInit(entry* h, entry* PQh);
float arrayToFloat(char part[]);
int main()
{
node *temp = 0, *head = 0;//starts out empty
node *PQt = 0, *PQh = 0, *PQp = 0;//Polish queue
float fltval;
int j, n = 0, flag, count = 0;
char string[80];
cout << "Enter an algebraic equation in reverse polish notation: \n";
cin.getline(string, 80);
cout << "Output from func arrayToInt:\n";
while(string[n] != '\0')
{
char part[15] = {'O'};
for(j = 0, flag = 0; (string[n] != ' ') && (string[n] != '\0'); j++, n++)
{
part[j] = string[n];
if(!isdigit(part[j]))//if character
{
flag = 1;
}//if
}//for
n++;
if(flag == 0)//if part consists of int
{
if(string[n] != '\0')
{
fltval = arrayToFloat(part);//converting array based number to float
cout << fltval << endl;
head = new node;
head->num = fltval;
head->type = 'N';
head->next = temp;
temp = head;
}//if
}//if
else
{
if(string[n] != '\0')
{
head = new node;
head->opr = part[0];
head->type = 'O';
head->next = temp;
temp = head;
}//if
}//else
}//while
//PQh = PQInit(head, PQh);
cout << "Output from linked list:\n";
printList(head);
//creating PQ stack from initial array
while(head != 0)
{
PQh = new node;
if(head->type == 'N')
{
PQh->num = head->num;
PQh->type = 'N';
PQh->next = PQt;
PQt = PQh;
}//if
else
{
PQh->opr = head->opr;
PQh->type = 'O';
PQh->next = PQt;
PQt = PQh;
}//else
head = head->next;
}//while
cout << "Output from PQ: \n";
printList(PQh);
return 0;
}//main
/***************************************/
//Prints list of Nodes
void printList(const node* pointer)
{
while(pointer != 0)
{
if(pointer->type == 'N')
cout << pointer->num << " ";
else
cout << pointer->opr << " ";
pointer = pointer->next;
}//while
cout << endl;
}//printList
/****************************************/
//Converts an array of ints to a float value
float arrayToFloat(char part[])
{
int L = 0, i, j;
float val = 0, value[15] = {0};
float valtab[5] = {1, 10, 100, 1000, 10000};
// 1 2 3 4 5
for(i = 0; part[i]; i++)
{
value[i] = part[i] - '0';//converting to int from char
}//for
L = strlen(part);
for(i = 0, j = L - 1; i < L; i++, j--)
{
val = val + (value[i] * valtab[j]);
}//for
return val;
}//arrayToFloat
When I originally started working on making the second stack, I was working on it in a separate function, but I got a ton of errors and just decided to get it working first in main. Just be ware this is very dated function, I am better off copying what I have in main into the function rather than this. I am posting this so you guys can see if I did anything wrong and so you can correct me before I update this function. Any tips to help me with this will be appreciated. Here is the (commented out) function code:
Code:
/******************************************/
//Initializes PQ
/*
entry* PQInit(entry* h, entry* PQh)
{
node* head = h;
while(h->next != 0)
{
if(h->type == 'N')
PQh->num = head->num;
else
PQh->opr = head->opr;
head = head->next;
PQh = PQh->next;
}//while
return h;
}//PQInit
*/
Thanks for all your help!