+ 1

How to use cin inside while loop.

I need explanation how to use cin inside while loop and when do we need to use it.

12th Nov 2019, 5:40 PM
Hana
5 odpowiedzi
+ 5
1. You can't do that on sololearn. 2. Just add the cin inside the while loop, and the program will always wait you to write something. Example: int i; do{ cin>>i cout<<"num is smaller than 100"; } while(i<100); (Btw, idk if this code actually works.)
12th Nov 2019, 5:48 PM
🍇 Alex Tușinean 💜
🍇 Alex Tușinean 💜 - avatar
+ 4
Well, you use cin inside a while loop when you need the user to enter a value that will be used after that, in the same loop. Everytime the loop runs, the user can chose something else. For example, calculating x*y. You could do an while loop, and user asked to enter x and y(for how many times he want), and if he enters 0 for example, to exit the program.
12th Nov 2019, 5:53 PM
🍇 Alex Tușinean 💜
🍇 Alex Tușinean 💜 - avatar
+ 3
int ch = 0; while(ch != -1) { cin >> ch; } This loop will keep iterating until the user don't enter -1.
12th Nov 2019, 6:17 PM
blACk sh4d0w
blACk sh4d0w - avatar
+ 1
It’s not only for here i need to know for my exam where to write
12th Nov 2019, 5:49 PM
Hana
+ 1
● How to use `cin` inside a `while` loop? int n; // Repeat while input stream // succeeds in reading input while(cin >> n) { cout << n << endl; } // Loop until a certain condition is satisfied while(true) { cin >> n; // exit loop if input invalid or an // I/O error occurs. if(!cin.good()) break; cout << n << endl; } ● When do we need to use it? We need it when we want to read input many times. Rather than writing `cin >> n; ten times for example, we can setup a loop to deal with the repetitive works. We also use `cin`, in a loop to get values for array elements. In this case, we use the subscript operator [] to tell C++ which element is about to be assigned a value. int i = 0, arr[5] {0}; // Repeat until all five array // elements had been assigned a value while(i < 5) { cin >> arr[i]; cout << arr[i] << " "; i++; } NOTE: Use of input in a loop is not supported in SoloLearn.
13th Nov 2019, 12:47 AM
Ipang