C++ program to check if a number is positive or negative has been shown here. A number n is said to be positive if it is greater than 0 i.e. n > 0 and it is considered as negative if it is less than 0 i.e. n < 0. If n = 0 then it is neither positive nor negative.

The following sections cover C++ program to determine if a number is positive or negative by using the above logic.

Page content(s):

1. Algorithm

2. Pseudocode

3. Time Complexity

4. Program & output

1. Flowchart

1. Algorithm to check if a number is positive or negative

// $n$ is an input number//

1. If $n\gt0$, then Return Positive else

2. If $n=0$, then Return Neither positive nor negative else

3. Return Negative

2. Pseudocode to check if a number is positive or negative

Input: A number $n$

Output: If $n$ is positive or negaive

1. Procedure positiveOrNegative($n$):

2. If $n\gt0$:

3. Return positive

4. Else:

5. If $n==0$:

6. Return Neither positive nor negative

7. Else:

8. Return negative

9. End Procedure

3. Time complexity to check if a number is positive or negative

Time Complexity: O(1)

4. C++ Program to check if a number is positive or negative

Code has been copied
/********************************************************
alphabetacoder.com
C++ program to check if a number is positive or negative
*********************************************************/

#include <iostream>

using namespace std;

int main() {
// declare variable
int n;

//take input
cout << "Enter the number = ";
cin >> n;

//check if n is postive or negative
if (n > 0)
cout << n << " is positive";
else {
if (n == 0)
cout << n << " is neither positive nor negative";
else
cout << n << " is negative";
}

return 0;
}


Output

Case 1:

Enter the number = -9

-9 is negative

Case 2:

Enter the number = 11

11 is positive

Case 3:

Enter the number = 0

0 is neither positive nor negative