i wrote a program using pointers in a basic stack program below is the pop and push functions and their calls in main. basically getting random numbers and converting to char characters and inserting them into an int array.
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
[Code]....
I am trying to use pointers in a stack program. But i am failing. my push function takes in the array,item im pushing, the reference to the top, and the size of the array.
void push(char stack[], char item, int *top, int max_size) {
if(&top==(max_size-1)) {
printf("Stack is Full");
return;
} else {
*top=+1;
stack[*top]=item;
} return;
}
And in the main function i pass a randomly pick char value, print it first , and pass it to the array using the push function
#define STACK_SIZE 10
#define STACK_EMPTY -1
int main(){
char s[STACK_SIZE];
int s_top = STACK_EMPTY; // The index of the top of the stack
int *top= s_top;
int max_size=STACK_SIZE;
[Code] .....
I know I am not referencing and dereferencing correctly and probably other stuff also. but i get these 2 errors:
stack.c: In function "push":
stack.c:23:9: warning: comparison between pointer and integer [enabled by default]
if(&top==(max_size-1))
[Code] ....
How can I use "delete[]" on all pointers on the stack, using a mixture of top and pop functions or variables
View 2 Replies View RelatedIn c89/90 is there a way to retrieve a pointer from stack or whatever that would behave as this would once cast to the correct type? This is more of a curiosity than a requirement.
View 6 Replies View RelatedI am trying to make a pointer to pointers for strings with malloc but my code isn't right.I tried something like that.
Code:
char **p;
**p=malloc(100*sizeof(char*));
for(int j=0;j<100;j++)
*(p+j)=malloc(10*sizeof(char));
how could i allocate memory is only needed for every string(as long as it is)? Cause in my code i allocate memory for 100 strings and for 10 characters for every string.
I'm just trying to get a handle on the uses of pointers here. Though clearly from my errors I'm missing a key concept. Here is my code: (You can assume that the array, "array_size" has values in it, I did this part in another function)
int main() {
bool **ptr_array;
int num;
int *array_size;
cin>>num;
[Code] ....
Once the program reaches the word[num] = false; some unhandled exceptions pop up.
I simplified my code a bit from my actual program and mixed up the loops, now the code should be in its correct form.
i'm still unclear between the difference between using pointer and a reference
I understood the concept of pointers in c in the class i took last year
and that was to change the actual value stored in the memory address Code:
void change_a(int a*){
a=6;
}
int main(){
int a=5;
change_a(&a);
}
but in c++ I've been using references in all my assignments because I don't know how to correctly use pointers in c++ I may have missed a class but I'm on spring break and would like to clear things up
so in c++
in my assignments I would call it like this Code:
void change_a(int &a){
a=6;
}
int main(){
int a=5;
change_a(a);
}
so does this change the value in the address or does it make another copy of a in my c++ code and stores 6 in that copy
I am having following pointer variable declaration
Code: Static double (*funcs[]) (double) = { sin,cos,tan,asin,acos};
Here funcs is an array of pointers to functions which take double as input and gives double as output with static as storage type am I right.
i try to write a postfix calculator program using stack in C++ the in put must be the infix expression but can dont know how to write a infix expression in put.
this is my code :
#include <iostream>
#include <stdio.h>
#include <math.h>
#include <conio.h>
using namespace std;
}
[code]....
I am trying to make an interpreter. This stack function is supposed to represent the scope of the program, meaning scope of the variables. The START represents a new scope, and FINISH represents the current scope closing. I am trying to do a recursive function in which the stack is updated with each recursive call, which represent a new scope for each call.After i enter a new scope and the scope ends, my program prematurely terminates.
void stack(ifstream& file,Hash& Table) {
string line;
getline(file,line);
int i=0;
[code].....
I keep getting the same error messages every time on Visual Studio. I don't know where the error is originating. Basically I'm trying to convert an infix expression (A+B-C) to a postfix expression (AB+C-) using stacks.
#include <iostream>
#include <fstream>
#include <string>
#include <stack>
#include "Expression.h"
#include "stackType.h"
using namespace std;
int main() {
string fileName;
string infixExpression, postfixExpression;
[Code] .....
How to write a programme that take strings from file and push it into the stack with number of each sting string before it and later clean the stack?
View 6 Replies View RelatedWrite a program that evaluates postfix expression using array implementation of stack.
The expression [the input] is evaluated from left to right using a stack. When the element read from the expression is an operand, push it into the stack.When the element read from the expression is an operator: Pop two operands from the stack.Evaluate the two operandsPush the result of the evaluation into the stack.
The final result lies on the top of the stack at the end of the calculation. Make sure to display the result before terminating the program.Write a program that evaluates postfix expression using array implementation of stack.
Code:
#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#define M 20
typedef struct{
[Code] ....
I know that if the structure doesn't fit into the stack, it needs to be put onto the heap. But what is maximum size of a win32 stack in usual case?
View 4 Replies View RelatedMy objective is to write a payroll program that among other things sorts the net pay by using pointers. I've already written most the program and have written a working program that sorts the net pay just not by pointers. So What I'll be posting below is my program so far without the pointer sort function.
What I need to do to finish my program is figure out how to add pointers to sort net pay into it.
#include <iostream>
#include <fstream>//file input output stream
#include <iomanip>
#include <string>
using namespace std;
//function prototypes
int readalldata(long int id[], string fname[], string lname[], int hoursworked[], float hourlyrate[], int n);
[Code] ....
As part of my ongoing c programming education, I have written a program to use void pointers in a function,
Code:
#include <stdio.h>
#define MAX_NUMBERS 10
size_t size(void *object);
int main(void) {
}
[code]....
Now I think that the result 4 is the size of the pointer, so I'm confussed as why it doesn't give me the same result as 40.
Code:
#include <stdio.h>
void Swap(int *x, int *y);
int *Largest(int *array, int size);
int main()
{
int a, b, i;
int c[10];
int maxaddress;
}
[code]...
My swap function works fine, but I am trying to find the ADDRESS of the largest element in my array and I am getting an error using gcc on my "return &largest;" and my printf line in my main function.How can I fix this and return the address of the largest?
Write following functions
makingArray: this function will return a double pointer which points to a double array and take one parameter- an integer variable which has a default argument of 5. The argument is the size of the integer array. when the function is called, the users input or default argument will be used for the size of the array. The function will initialize all elements of the array with the 'cin' object.
getTotal: this function will return a double and take two parameters- a double array, which can NOT be modified by this function, and an integer variable for a size of the array. This function will calculate the total of all elements then return a double number which is the total.
main: demonstrate functions( makingArray and getTotal) by calling them in a program
I have created a program that allows for a user-defined number of test scores as input. After the user enters these scores, the program calculates the average test score. Here is my code:
#include <iostream>
#include <iomanip>
using namespace std;
// Function prototypes
double getAverage(double*, int);
[Code] .....
I am having trouble with the final part of my program. How do I pass the array of test scores to a function that calculates how many people got an A (90+) on the test? The final output should look like this:
The average of those scores is:
The number of A grades is:
The assignment is to create a program that displays the median of an array using pointers. Assume the array is already in ascending or descending order.I'm getting errors currently on the bottom two "return median;" statements.The code that I have so far is as follows...
#include <iostream>
using namespace std;
char again;
int getMedian(int*, int);
const int constant = 100;
[code]....
I am writing a class that dynamically allocates an array that holds a user-defined number of test scores (test scores go from 0 to 10 both included). Once all the test scores are entered and validated (values only between 0 and 10, both included), the array should be passed to a function that sorts them in ascending order. Another function should be called that calculates theaverage of all the scores.The main program should display the sorted list of scores and the average of the scores with appropriate headings.
View 6 Replies View RelatedI'm trying to create an array of pointers to pointers which will point to array of pointers (to strings) I tried
Code:
int i;
char *string[]={
"my name is dave",
"we like to dance together",
"sunny day",
"hello",
[code]...
the app keeps crashing , I don't know how to make the array-elements to point to another array-elements..
I am a little confused while comparing char pointers to integer pointers. Here is the problem:
Consider the following statement;
char *ptr = "Hello";
char cArr[] = "Hello";
When I do cout << ptr; it prints Hello, same is the case with the statement
cout << cArr;
As ptr and cArr are pointers, they should print addresses rather than contents, but if I have an interger array i.e.
int iArr[] = {1, 2, 3};
If I cout << iArr; it displays the expected result(i.e. prints address) but pointers to character array while outputting doesn't show the address but shows the contents, Why??
I have not been using pointers that long i most of my stuff has not needed them but now they do i need to learn how to use them more. I'm writing a program that simulates the squares most landed on(for fun) and i cant get a method to work because of an array pointer.
The error is no matching function for call to 'GameLoop::Loop(int, int (*)[4])'
Here is the latest version of the code. I've been editing a lot of things so there might be some stupid errors but I've tring everything.
rolling.h and rolling.cpp are just some dice function they are working perfect.
main.cpp
#include <iostream>
#include "Rolling.h"
#include "GameLoop.h"
Rolling Roll;
GameLoop Game;
[Code] ....
I am working on a program which creates a large pointer array of numbers and then performs several iterations of operations in them.
Code:
int * u = new int[N];
double * nu = new double[N];
int * nud = new int[N];
for (int i=0;i<M;i++){
for (int i=0;i<N;i++){
u[i]=0;
nu[i]=0;
[Code]...
If M is small enough then there are no problems in the program. However once M is large enough I get the "unhanded exception":
std::bad_alloc at memory location 0x0026f728..
Since I am just reusing the same arrays, and since I am able to make it through a few iterations, I didn't think it could be a memory issue. If it is, is there a way I can clear the data completely after each iteration?
I was having problems changing the value of my head node I passed it as an argument as head which would be the address. The parameter was defined as struct node *head. like this
bool deleteNode(struct node *head, struct node *delptr)
I tried manipultaing pointer values to change head node value but it did not work. I saw some code online which used pointer to pointers(in code below) to change head node value it worked I dont fully understand why. Would like better understanding of why.
Would also like to know why the argument call needed &head instead of just head.
remove = deleteNode(&head,found); opposed to remove = deleteNode(head,found);
#include "stdafx.h"
#include<iostream>
struct node{
[Code].....