How to make a dynamic array? Two parameters

Perhaps this snippet can help:

    vector<int> x;

    int size;
    cin >> size;

    while (size--)
    {
        int temp; cin >> temp; x.push_back(temp);
    }
/*
    Better is, but the compiler dislikes it:
    while (size--)
        cin >> x.push_back();
    or
    while (size--)
        x.push_back(cin>>);
*/ 

    // processing...

    for (vector<int>::iterator it = x.begin(); it != x.end(); it++)
        cout << *it << endl;

    x.clear();

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

int main()
{
	int size;
	scanf("%d",&size);
	int* p = (int *)malloc(sizeof(int)*size);
	if(NULL == p)
		exit(-1);
	for(int i = 0;i < size;++ i)
		scanf("%d",&p[i]);
	for(int i = 0;i < size;++ i)
		printf("%3d",p[i]);
	return 0;
}</stdlib.h></malloc.h></stdio.h>

int main()
{
  int size;
  int *ptr_arr;          //pointer delaration
  cin>>size;             //input size from user
  ptr=new int[size];     //array declared in heap or dynamic memory
  for(int i=0;i<size;i++)>
     cin>>ptr_arr[i];        //takes input in dynamic array
  for(int i=0;i<size;i++)>
     cout<<ptr_arr[i];

return 0;
}

I hope it helps

The only way to make a two dimension without the use of the advanced C++ features is the use an array of pointers, note the two for loops, one is for initialization, and the second is for cleanup purposes.

Example:

#include <iostream>
using namespace std;

int main()
{
	int **a;
	int i = 0, j = 0;
	int k;

	cout << "input dimension 1:";
	cin >> i;
	cout << "input dimension 2:";
	cin >> j;

	a = new int *[i];
	for (k = 0; k < i; k++)
	{
		a[k] = new int[j];
	}
	
	cout << "a[0][0]: ";
	cin >> a[0][0];
	
	a[0][0] = 1024;
	cout << "value: " << a[0][0] << endl;

	for (k = 0; k < i; k++)
	{
		delete a[k];
	}
	delete  a;

	return 0;
}

Array declaration in C/C++ will not be success if you don't provide a constant size. For the beginners who do not familiar with pointers the following may give a good understanding.

1. Declare an array with a maximum size; when your input exceeds this limit you can always show an error message.
int x[100];

2. when you deal with an array size within the maximum size, keep the dynamic size in a variable and use the variable as the size of your array instead of the maximum size.

int main(){
   int x[100];  //maximum size is 100
   int size;
   cin>>size;   //to accept the size
   if (size>=100){
      cout<<"Array size exceeds the maximum allocation";
      return 0;
   }
   //when inputting numbers
   for(int i=0; i<size; i++){
      cin>>x[i];
   }
   //when displaying the result
   for(int i=0; i<size; i++){
      cout<<x[i]<<endl;
   }
   return 0;
}

Hope this will help.

have a good time dear mr sajjad
you're from iran?me too.

look you have to declare a dynamic array like above:

int n=0,*a=0;
cout<<"enter the length of array :\n";
cin>>n;
a=new int[n];

after that you can control the array with an index , like above :

int j=0;
j=a[7];

good lock and god with you