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Question

I'm relatively new to C++ and we have been given this task to do:

Write a C++ program which asks the user for a number n between 1 and 10. The program should then print out n lines. Each should consist of a number of stars of the same number as the current line number. For example:

 Please enter a number: 5 * ** *** **** *****

The problem I am having is that when I use the code I've written it displays wrong.

The code I have right now reads like this:

#include<iostream>

using namespace std;

int main() {

    int n;
    cout << "Please enter a number between 1 and 10:" << endl;
    cin >> n;


    for (int x = 0; x <= n; x++)
    {
        for (int y = 0; y <= n; y++) {
            cout << "*" ;
        }
        cout << "*" << endl;
        cin.get();
    }

    return 0;
}

Answer 1

Step through the logic of your program using pen and paper.

For your "horizontal" loop, you go all the way up to n each time. Is that right? I think you meant to go only as far as x , as this is the value that increases with each line.

The other problem is that you have one too many of everything, because you used <= rather than < .

Answer 2

The solution is exactly as '@Lightness Races in Orbit' just explained to you. Let me add that if the requirement is just print out what you showed us, then no need for the last '*' nor the 'cin.get()':

for (int x = 0; x <= n; ++x)
{
    for (int y = 0; y < x; ++y) {
        cout << "*" ;
    }
    // No need for all the rest just print 'new line'
    std::cout << "\n";
}

Try it live!

Answer 3

There is no need for a nested loop. This program works as well with one for loop.

#include <iostream>
using namespace std;


int main()
{
    int n = 0;
    cout << "Enter a number and press ENTER: ";
    cin >> n;
    for (int i = n; i < 11; ++i) {
        cout << i << " " << endl;
    }


    return 0;
}