Question

This is in C++ Write a program that reads a string consisting of a positive integer or a positive decimal number and converts the number to the numeric format. If the string consists of a decimal number, The program must use a stack to convert the decimal number to the numeric format. I keep getting an error around line 31 stating that there is an undefined function stObj.push(*it - 48); -- any help to fix my error would be helpful, thank you in advance.

Here is my code:

#include <iostream>
#include <string>
#include <stack>
#include <math.h>
using namespace std;

//main method
int main()
{
   //Declare local variables
   string input;
   double number = 0;
   int index = 0;

   //declare the stack of type integer
   stack<int> stObj;

   //prompt and read the input number
   //of type string
   cout << "Enter a decimal number:";
   cin >> input;

   //declare iterator
   string::iterator iterObj = input.begin();

   //push the number into the stack
   //increment the index of the stack
   while (*iterObj != '.' && iterObj != input.end())
   {
       //push into the stack
       stObj.push(*it - 48);
       iterObj++;
       index = index + 1;
   }

   //compute the integral part of the number
   for (int i = 0; i < index; i++)
   {
       number = number + (stObj.top()*pow(10, i));
       stObj.pop();
   }

   //consider the fractional part
   index = -1;
   if (iterObj != input.end())
   {
       //increment the interator for the memory address
       iterObj++;
   }
   //compute the fractional part to number
   while (iterObj != input.end())
   {
       number = number + ((*iterObj - 48)*pow(10, index));
       index = index - 1;
       iterObj++;
   }
   //Display the decimal number
   cout << "The numeric format: " << number << endl;
}

Answer 1

Correct C++ Code:

#include <iostream>
#include <string>
#include <stack>
#include <math.h>
using namespace std;

//main method
int main()
{
//Declare local variables
string input;
double number = 0;
int index = 0;

//declare the stack of type integer
stack<int> stObj;

//prompt and read the input number
//of type string
cout << "Enter a decimal number:";
cin >> input;

//declare iterator
string::iterator iterObj = input.begin();

//push the number into the stack
//increment the index of the stack
while (*iterObj != '.' && iterObj != input.end())
{
//push into the stack
stObj.push(*iterObj - 48);
iterObj++;
index = index + 1;
}

//compute the integral part of the number
for (int i = 0; i < index; i++)
{
number = number + (stObj.top()*pow(10, i));
stObj.pop();
}

//consider the fractional part
index = -1;
if (iterObj != input.end())
{
//increment the interator for the memory address
iterObj++;
}
//compute the fractional part to number
while (iterObj != input.end())
{
number = number + ((*iterObj - 48)*pow(10, index));
index = index - 1;
iterObj++;
}
//Display the decimal number
cout << "The numeric format: " << number << endl;
}

Bold change has to be made in your code.

*it is not defined.

It should be changed to *iterObj.

Output: