[SOLVED] C++ while problem.

iceman81 · 07-23-2016, 12:05 PM

hey guys, i am working my way through C++ primer 5th ed. and in the first chapter it gives a problem to solve.

problem: write a program that prompts the user for two integers. Print each number in the range specified by those two integers.

I was really dumbfounded at first, as this was different from the examples before. So i searched online for an example to go through, and they used the "Print_Range" function.

Now at this early in the book, there is no mention of this function, so I conclude that that can't be what they are looking for.

Here is my code that i came up with, which I don't think is 'correct', but it gets the job done.

Also- I am using while loop, because that was the last topic before this question.

Code:

#include <iostream>
int main()
{
  int v1 = 0, v2 = 0;  //setting 2 variables for cin
  std::cout << "Please enter 2 integers: " << std::endl;
  std::cin >> v1 >> v2; 
  std::cout << "The numbers between " << v1 << " and " << v2 << " are: "
	    << std::endl;
  int v3 = v2 - 2; // while loop was going over v2, added v3 to compensate.
  while(v1 <= v3) {
    ++v1;
    std::cout << v1 << std::endl;
  }

  return 0;
}

keefaz · 07-23-2016, 12:43 PM

You have to determine first which variable (v1 or v2) has the least value, then count from it until the other value
Assigning least and greatest values to start and end variables could be useful

I would use a for loop instead as it tests variable value and increments, while while loop requires another line (like in your code)

iceman81 · 07-23-2016, 12:52 PM

thanks for responding, the section on 'for' is directly after, and it does make much more sense. Maybe moving forward i'll wait to finish the chapter to try the exercises =P. thanks again.

keefaz · 07-23-2016, 01:30 PM

Just another thought, you can also write the increment in the while loop

Code:

while(++v1 <= v3) {
    std::cout << v1 << std::endl;
}