C/C++ C++: Using a for loop to print a countdown

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The discussion centers around writing a C++ program that prints a countdown from a user-defined number to one, followed by "Blastoff!". The initial code provided incorrectly resets the value of `userNum` within the for loop, leading to incorrect outputs. The corrected code uses a separate variable, `i`, initialized to `userNum`, which decrements until it reaches zero, ensuring the correct countdown is printed. The output format is confirmed to be correct, with each number and "Blastoff!" printed on a new line. Additionally, the thread was edited for clarity and readability.
needOfHelpCMath
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Write code that prints: userNum ... 2 1 Blastoff! Your code should contain a for loop. Print a newline after each number and after Blastoff!. Ex: userNum = 3 outputs:
3
2
1
Blastoff!

Code:
#include <iostream>
using namespace std;
int main() {
   int userNum = 0;
   int i = 0;
   userNum = 3;
   i = 1;
   for (userNum = 3; 1 <= userNum; --userNum) {
   cout << userNum << endl;   
   
   }
 cout << "Blastoff!" << endl;
   return 0;
}

Run
Testing with userNum = 3.
Your output: 3
2
1
Blastoff!
✖ Testing with userNum = 1.
Expected output: 1
Blastoff!
Your output: 3
2
1
Blastoff!
 
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Re: So close what is wrong with my program

You are resetting the value of [m]userNum[/m] when you begin the for loop. This is how I would write the program:

Code:
#include <iostream>
using namespace std;
int main()
{
	int userNum = 3;
	int i;

	for (i = userNum; i > 0; i--)
	{
		cout << i << endl;   
	}

	cout << "Blastoff!" << endl;
	return 0;
}

Please note that I have edited your thread title to describe the nature of the question being asked, and enclosed your code in the [CODE][/CODE] tags so that whitespaces are preserved and the indentation will enhance readability. :)
 
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