Creating a loop in C++ (still learning)

As already said by pb772 an infinite loop of type

do { //Stuff you'd like to do } while(1);

would be fine, especially since it's a school assignment, but not ideal as always stated by pb772. I've seen advises to cycle a finite number of times and then exit but I would instead do something like a special character like '#' or '!' that will trigger a condition to exit the loop. I would see this like an exit/escape character. In the end is up to you, if you want you can do anything and what I'm proposing is just an idea to inspire you. For example another idea would be, if you'd like to go deeper, wait for another input to define what action to perform, you trigger the "command console" with '!' and then type 'q' to exit or also read the characters into a string at first so you could do complex "commands" like "!q".

Here's the simple version:

bool loop_condition = true; do { if(input == '!') { loop_condition = false; } else { //Stuff you'd like to do if the read character is not ! }while(loop_condition == true); 

Just to provide context here is what's happening:

1. I declare a variable named loop_condition
2. Inside the loop I check if the typed character is !
3. If so set the variable loop_condition to false with subsequent exit from the loop
4. Else just execute your code and loop

As I already said this is a very simple example just to give you an idea and can be improved a lot.

I suggest wrapping the for (counter=0... loop with a while (!cin.eof()) { block. This will allow the user to continue to enter in characters, until an EOF character (e.g. ctrl-D).

You may find you want to output a newline after every 7th character, to make the display look nice.

do { //your code here; } while (1); 

This will repeatly infinitely which is not a good practice.

int number_of_phones = 10; // total number of phones you want int i = 0; do { //your code here; i=i+1; } while (i<number_of_phones); 

This will make it run 10 times for example

You can have whatever condition you want in a for loop, including nothing at all, which is treated as true.

for(;;) { // code } 

is the same as

while (true) { // code } 

is the same as

do { // code } while (true) 

It sounds like you mixed up the placement of braces when you tried do { ... } while (true). You may want to move your big switch into a function, so that it's more obvious what scope a partiular } ends.

#include <iostream> int phone_key(char key) { switch (key) { case 'A': case 'a': case 'B': case 'b': case 'C': case 'c': return 2; case 'D': case 'd': case 'E': case 'e': case 'F': case 'f': return 3; case 'G': case 'g': case 'H': case 'h': case 'I': case 'i': return 4; case 'J': case 'j': case 'K': case 'k': case 'L': case 'l': return 5; case 'M': case 'm': case 'N': case 'n': case 'O': case 'o': return 6; case 'P': case 'p': case 'Q': case 'q': case 'R': case 'r': case 'S': case 's': return 7; case 'T': case 't': case 'U': case 'u': case 'V': case 'v': return 8; case 'W': case 'w': case 'X': case 'x': case 'Y': case 'y': case 'Z': case 'z': return 9; } return 0; } int main() { for (;;) { std::cout << "\nEnter a phone number in letters only." << std::endl; for (int counter = 0; counter < 7; counter++) { char phoneNumber; cin >> phoneNumber; if (counter == 3) std::cout << "-"; std::cout << phone_key(phoneNumber); } } }