Program will not exit a do-while loop

Question

I'm trying to make a simple calculator in C++. Here is a portion of the code:

#include <iostream>
#include <string>
#include <cmath>

using namespace std;

int main()
{
    int math;
    int a1;
    int a2 = 0;
    int a3 = 1;
    int answer;
    int amount = 0;
    int achecker = 1;

    cout << "Welcome to my calculator! Type '1' to add, type '2' to subtract, "
            "type '3' to multiply, type '4' to divide, and type '5' to exit."
         << endl;
    cin >> math;

    while (math = 1)
    {
        cout << "Input how many numbers you wish to add:" << endl;
        cin >> amount;
        achecker = amount;
        do
        {
            cout << "Input the number you wish to add:" << endl;
            cin >> a1;
            answer = a1 + a2;
            a2 = a1;
            achecker = achecker - achecker + 1;
        } while (achecker < amount);
        cout << answer;
    }

The problem I am encountering is that when the program gets into the do-while loop, it never comes out, it just keeps on asking for the user to input a number. I have gone over this several times and I have no idea what the problem is. Can someone help?

Answer 1

First of all , you should be writing while(math==1) sicnce math=1 is an assignment operator not a check operator.

Secondly, instead of while , use if since you want to do the calculation for addition only once , putting it in while loop will make it an infinite loop.

Thirdly , in the do - while loop , the condition should be while(achecker>=0), because your condition will always give a true value.So, actually , there is no need of achecker, simply keep decrementing amount by one for each loop run and keep the condition as while(amount>=0) .

One, more improvement i would like to suggest , though not required - declare answer as int answer = 0;. For each loop run , accept a new value in a1 and then for adding , write answer=answer+a1. This should serve your purpose.

So, edited code according to me should be -

#include <iostream>
#include <string>
#include <cmath>

using namespace std;

int main()
{
  int math;
  int a1;
  int a3 = 1;
  int answer = 0;
  int amount = 0;
  int achecker = 1;

  cout << "Welcome to my calculator! Type '1' to add, type '2' to subtract, type '3' to      multiply, type '4' to divide, and type '5' to exit." << endl;
  cin >> math;

  if(math == 1){
  cout << "Input how many numbers you wish to add:" << endl;
  cin >> amount;
  do{
  cout << "Input the number you wish to add:" << endl;
  cin >> a1;
  answer = answer + a1;
  amount = amount - 1;
  }while(amount>=0);
  cout << answer;
  }

Answer 2

You have wrong condition check in the while loop.

match=1 is assignment operation and not equality check, which is what you are trying to do. The assignment will always return 1(true) so you have an infinite loop.

replace match=1 with match==1 for your code to work

Answer 3

achecker = achecker - achecker + 1; is always equal to 1. So I think you have an error in that line.