Hello, the below code for the Towers of Hanoi problem was taken from class notes

Question

Hello, the below code for the Towers of Hanoi problem was taken from class notes. We were given the recursive and non-recursive solutions to the problem along with a solution that uses stacks.

For the stacks solution, I tried copying the code from various slides and then running it, but I had a few problems.

-> My compiler (DEV-C++) doesn't recognize "return TRUE" or "return FALSE". I'm not sure what to replace the TRUE and FALSE with..

Here is the code (it may be missing parts for all I know, but this is all that was in the notes):


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

#define DEFAULT_SIZE 7
struct stack{
int top;
int elements[DEFAULT_SIZE];
};

typedef struct stack stack;


//Function prototypes

stack init_stack(stack s, char *name);

int push(stack *s,unsigned int i);

int pop(stack *s);

int isempty(stack s);

int isfull(stack s);

//Main function*************************************************************************

void
towersOfHanoi(int n, stack *src, stack *aux, stack *dst) {
if( n > 0 ) {
towersOfHanoi(n-1,src,dst,aux);
push(dst, pop(src));
print_state();
towersOfHanoi(n-1,aux,src,dst);
}
}

//Functions******************************************************************************


stack
init_stack(stack s, char *name) {
s.top = 0;
return s;
}
void
dispose(stack s){
free(&s.elements);
free(&s);
}

int
push(stack *s, unsigned int i) {
if(isfull(*s)){
printf("Warning: Push on full stack ");
return FALSE;
}
s->elements[s->top] = i;
s->top++;
return TRUE;
}
unsigned int
pop(stack *s) {
if(isempty(*s))
printf("Warning: Pop from empty stack ");
s->top--;
return s->elements[s->top];

int
isempty(stack s){
if(s.top == 0)
return TRUE;
else
return FALSE;
}
int
isfull(stack s){
if(s.top < DEFAULT_SIZE - 1){
return FALSE;
}
else
return TRUE;




I would appreciate any help with editing the code so that it runs.

Thanks

Explanation / Answer

You are missing a "main" function (the function that tells the program where to enter), as well as the "print_state()" function. I have altered the program to a point where it will compile and execute, but it will not print anything because I do not have "print_state" (I made a blank function) as well as the implementation of calling the function "towersOfHanoi" (which would go in the blank "main" function that I created). Here is the code (let me know if you need anything further): #include #include #define DEFAULT_SIZE 7 struct stack{ int top; int elements[DEFAULT_SIZE]; }; typedef struct stack stack; //Function prototypes stack init_stack(stack s, char *name); int push(stack *s,unsigned int i); unsigned int pop(stack *s); int isempty(stack s); int isfull(stack s); void print_state(); //Main function************************************************************************* void main() { } void towersOfHanoi(int n, stack *src, stack *aux, stack *dst) { if( n > 0 ) { towersOfHanoi(n-1,src,dst,aux); push(dst, pop(src)); print_state(); towersOfHanoi(n-1,aux,src,dst); } } //Functions****************************************************************************** void print_state() { } stack init_stack(stack s, char *name) { s.top = 0; return s; } void dispose(stack s){ free(&s.elements); free(&s); } int push(stack *s, unsigned int i) { if(isfull(*s)){ printf("Warning: Push on full stack "); return false; } s->elements[s->top] = i; s->top++; return true; } unsigned int pop(stack *s) { if(isempty(*s)) printf("Warning: Pop from empty stack "); s->top--; return s->elements[s->top]; } int isempty(stack s){ if(s.top == 0) return true; else return false; } int isfull(stack s){ if(s.top

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