ETH_Informatik/Informatik_I/Exercise_3/Task_2

Task 2: Loop mix-up: Snippet 2

• Task
• Solution

This task is a mixed text/programming task. You need to update the content of loop.cpp according to the instruction provided in the file. For the code part, please check the autograder output.

Task

Considering the snippet

for (;;) {
  int i1, i2;
  std::cin >> i1 >> i2;
  std::cout << i1 + i2 << "\n";
  int again;
  std::cout << "Again? (0/1)\n";
  std::cin >> again;
  if (again == 0) break;
}

1. Describe what it computes.
2. Decide which of the other two kind of loops would fit better than the one it is currently using, and describe why.
3. Rewrite the snippet into the loop you specified in (2). This part is autograded. Note: print the control message "Again? (0/1)" using the same format used in the snippet.

Solution

#include "loop.h"
#include <iostream>

// Fill out the file with the required answers

/*

  Subtask 1: describe what the code snippet computes

  It is a very simple calculator which adds up the 2 number which are inputed by
  the user.

*/

/*

  Subtask 2: decide which of the other two kind of loops would fit better, and
  describe why.


  A while loop would be sufficient for the task of this code snippet, since we
  only have to check, if the user wants to use the calculator again or not.

  Of course, as in the last task we could look at the edge case. We could also
  add an if expression to elimnate the posibility to input other numbers other
  than 0 and 1 for the again variable.

*/

/*
  Subtask 3: update the function below by rewriting the snippet into the
  loop you specified in (2).
  Note: print the control message "Again? (0/1)" using the same format used
  in the snippet.
*/

void loop() {

  int again = 1;

  while (again != 0) {
    int i1, i2;
    std::cin >> i1 >> i2;
    std::cout << i1 + i2 << "\n";
    std::cout << "Again? (0/1)\n";
    std::cin >> again;
  }
}

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Made by JirR02 in Switzerland 🇨🇭