C++ program to detect a negative input (logic explained)

Here is the C++ code to detect a negative input . It takes input from user until a negative number is entered and it shows the message for negative number.. You all should have in mind how it works exactly. Here is the algorithm.

  Steps

User side

1: User asked to enter a number

2: If the number is negative, screen displays a message that the number is negative.

3: Otherwise user again asked to enter a number.

Developer side

1: Declare variables that are going to be used in program .

2: Start a do while loop.

3: In the loop input a number from user

4: In the while statement place a condition (n>=0) that is number should be positive.

5: Program ends here.

Code:

#include<iostream>

using namespace std;

int main(){

       //declaraton of varables

       int n;

       do

       {

              cout<<"Enter a positve number = ";

              cin>>n;

       }

       while(n>=0);

       cout<<"You entered a negatve number so program is ended"<<endl;

    system("pause");

    return 0;

}

Output: