libreria
 #pragma once

#include <iostream>

using namespace System;
using namespace std;

int Menu() {
	int opt;

	cout << "Menu de opciones" << endl;
	cout << "1. Ingresar elemento." << endl;
	//cout << "2. Buscar elemento." << endl;
	//cout << "3. Eliminar elemento." << endl;
	do {
		cout << "Ingrese una opcion: ";
		cin >> opt;
	} while (opt < 0 || opt > 6);
	return opt;
}

int* IAF(int *arr, int *cant) {
	Random x;
	int *aux; aux = new int[*cant];

	for (int i = 0;i < *cant;i++) { aux[i] = arr[i]; }
	arr = new int[*cant + 1];
	for (int i = 0;i < *cant;i++) { arr[i] = aux[i]; }
	arr[*cant] = x.Next(10, 99 + 1);
	*cant += 1;

	return arr;
}

int* IAI(int *arr, int *cant, int *ind) {
	Random x;
	int *aux; aux = new int[*cant];

	for (int i = 0;i < *cant;i++) { aux[i] = arr[i]; }
	arr = new int[*cant + 1];


	do {
		cout << "Ingrese el indice del valor del dato: ";
		cin >> *ind;
	} while (*ind < 0 || *ind > *cant);
	for (int i = 0;i < *ind;i++) { arr[i] = aux[i]; }
	arr[*ind] = x.Next(10, 99 + 1);
	for (int i = *ind+1;i < *cant;i++) { arr[i] = aux[i]; }


	*cant += 1;

	return arr;
}

void Mostrar(int *arr, int *cant) {
	system("cls");
	for (int i = 0;i < *cant;i++) { cout << arr[i] << endl; }

}


pagina

#include <iostream>
#include <conio.h>
#include "Header.h"

using namespace System;
using namespace std;

/*
void Ingresar(int *x) {
	do {
		cout << "Ingrese la cantidad de datos: ";
		cin >> *x;
	} while (*x < 0);
	for (int i = 1; i <= *x; i++) {
		cout << "Ingrese el valor Num " << i << ": ";
		cin >> i;
	}
}
*/

void main() {
	int *opt = new int;
	int *arr;
	int *cant_ele = new int;
	int *ind = new int;

	*cant_ele = 0;

	do {
		*opt = Menu();
		if (*opt == 1) { arr = IAF(arr, cant_ele); }
		if (*opt == 4) { Mostrar(arr, cant_ele); }
		if (*opt == 5) { IAI(arr, cant_ele,ind); }

	} while (*opt < 6);



	cout << endl;
	system("pause>0");
	delete[] opt;
}