A challenging programming excercise for beginners

Question

So, I came across a challenging programming excercise. And I think it is a good practice for beginner/intermediate programmers.

"Write a program that outputs all possibilities to put + or - or nothing between the numbers 1,2,…,9 (in this order) such that the result is 100. For example 1 + 2 + 3 - 4 + 5 + 6 + 78 + 9 = 100."

Succes!

Answer 1

This is extremely easy, there are only 3^8 possibilities, hence brute force will work. Still a nice exercise for beginners.

Answer 2

I think this should be correct, but I did not really check it, as I'm quite tired right now. Quite a short and not too inelegant code, although the approach is rather naive:

https://code.sololearn.com/ctbncskQ1Nxi

Answer 3

@Krishneel Nair: I think you should read the problem again. All your code does is to print the numbers up to the user input and put alternating signs in between.

Answer 4

in C++

int user_input = 0;
cin >> user_input ;

for (int i = 1; i <= user_input; i++)
{
if (i == user_input )
{
cout << i << " = ";
}
else if (i % 2)
{
cout << i << " - ";
}
else
{
cout << i << " + ";
}
}

Answer 5

@Tobi You might be right. I change it to beginner