struct node
{
char data[100];
struct node* next;
};
int elements = 0;
// function for add values to stack
struct node* add(struct node* stack, char *str)
{
struct node* tp = (struct node*)malloc(sizeof(struct node)) ;
strcpy(tp->data,str);
tp->next = stack;
elements++;
return tp;
}
//redo function
void redo(struct node* stack)
{
if(stack == NULL)
return;
elements++;
}
//undo function
void undo(struct node* stack)
{
if(stack == NULL)
return;
elements--;
}
//print function
int print(struct node* stack,int idx)
{
if(stack == NULL)
return 0;
idx = print(stack->next,idx);
if(idx<>
printf("%s\n",stack->data);
return idx+1;
}
//function for save in file
int save_command(FILE* filePointer, struct node* stack,int idx)
{
if(stack == NULL)
{
return 0;
}
idx = save_command(filePointer, stack->next,idx);
if(idx<>
fprintf(filePointer,"%s\n",stack->data);
return idx+1;
}
//main function
int main()
{
//stacks for undo and redo
struct node *stack1 = NULL;
char input[100];
while(1==1)
{
printf("MyCommand > ");
gets(input);
if(strcmp("undo",input)==0)
{ //if input is undo
undo(stack1);
printf("result >\n");
print(stack1,elements);
}
else if(strcmp("redo",input)==0)
{ //if input is redo
redo(stack1);
printf("result >\n");
print(stack1,elements);
}
else if(strcmp("print",input)==0)
{ //if input is print
printf("result >\n");
print(stack1,elements);
}
else if(strcmp("save", input)==0)
{ //if input is save
FILE* filePointer;
filePointer=fopen("output.txt","w");
save_command(filePointer,stack1,elements);
fclose(filePointer);
}
else if(strcmp("quit",input)==0) //if input is quit
{
FILE* filePointer;
filePointer=fopen("output.txt","w");
save_command(filePointer,stack1,elements);
fclose(filePointer);
printf("result > Good Bye!\n");
exit(0);
}
else //if input is any other string add to stack
stack1 = add(stack1,input);
}
return 0;
}