my code is not running
My code that has to do with pointers is not running properly for some reason?
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#include <iostream>
#include <iomanip>
#include <assert.h>
#include <stdlib.h>
using namespace std;
struct Structure;
typedef Structure * structure_pointer;
struct Structure
{
int f1;
int f2;
structure_pointer f3,f4;
};
structure_pointer get_structure(int n, char ch);
void print_structure(structure_pointer p);
void tranverse_structure(structure_pointer p);
int main()
{
structure_pointer head,p,q;
head = new Structure;
head = get_structure(1,'a');
q=head;
for(int i=2; i<=10; i++)
{
p= get_structure(i, char('a' + -1));
q-> f3 = p;
q= q-> f3;
}
cout << endl;
cout << "Tranversing the whole structure " << endl;
tranverse_structure(head);
cout << endl;
return 0;
}
structure_pointer get_structure(int n, char ch)
{
structure_pointer temp = new Structure;
assert (temp != NULL);
temp -> f1 =4;
temp -> f2 = ch;
temp -> f3 = NULL;
temp -> f4 = NULL;
return temp;
}
void print_structure (structure_pointer p)
{
cout << endl;
cout << "f1 = " << setw(2) << (*p).f1 << "f2 = " << p -> f2;
if (p-> f3 !=NULL)
tranverse_structure (p->f3);
}
void tranverse_structure (structure_pointer p)
{
structure_pointer head,q;
tranverse_structure(head);
p = head;
for(int i=1; i<=10; ++i)
{
q=p;
p = p-> f3;
delete q;
}
}
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Please explain the "not properly".
This has grotesk memory leak:
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head = new Structure;
head = get_structure(1,'a');
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Structure::f2 is
int. You write
char to it. Not an error, but odd.
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structure_pointer head; // uninitialized
tranverse_structure(head); // use of uninitialized variable
p = head; // use of uninitialized variable
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structure_pointer get_structure(int n, char ch)
// unused parameter n
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... and then some.
In short: we cannot see what you expect to be "proper", but we can see many points that should crash and burn.
> int f1;
> int f2;
> structure_pointer f3,f4;
Utterly meaningless variable names.
You might get more clarity if you had say
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struct Structure {
int numberOfOccurrences;
char letter;
structure_pointer prev,next;
};
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At least you'd stand a chance of spotting silly mistakes like say
letter += 1; // huh?
prev = next; // huh?
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void tranverse_structure (structure_pointer p)
{
structure_pointer head,q;
tranverse_structure(head);
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Because calling yourself recursively without giving yourself an out, will always blow up.
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