Question

write a c++ code be sure the user only enter A or a for packageA, B or b for packageB, C or c for packageC. If the user inputs some other value display an error message saying " invalid out".

When you ask the user to input the number of minute and the user enters a negative value you should display the same error message "invalid input" in both cases, after you display the error

message the program should stop (exit). Please write the logic in c++ I'm writing a program and I want know how to write logic in my code.

Answer 1

Program in C++:-

#include<iostream>
using namespace std;

int main()
{
//This menu will show in the beginning of the program.
cout<<"'A' or 'a': For packageA"<<endl;
cout<<"'B' or 'b': For packageB"<<endl;
cout<<"'C' or 'c': For packageC"<<endl;
cout<<endl;
cout<<"Please enter your choice from the above menu: ";
//choice variable take the choice of user on above menu.
char choice;
cin>>choice;
//If A or a selected then it will print "You are in packageA".
if(choice == 'A' || choice == 'a'){
//In this section, you can add your own code that should be run in packageA.
cout<<"You are in packageA"<<endl;
}
//If B or b selected then it will print "You are in packageB".
else if(choice == 'B' || choice == 'b'){
//In this section, you can add your own code that should be run in packageB.
cout<<"You are in packageB"<<endl;
}
//If C or c selected then it will print "You are in packageC".
else if(choice == 'C' || choice == 'c'){
//In this section, you can add your own code that should be run in packageC.
cout<<"You are in packageC"<<endl;
}

//if user enters different character.
else{
cout<<"invalid out"<<endl;
//it will exit from the execution.
exit(0);
}

int minute;
cout<<"Enter the number of minute: ";
cin>>minute;
//when user input negative value of minute variable.
if(minute < 0){
cout<<"invalid input";
//it will exit from the execution.
exit(0);
}

//here, you can add your code after checking the negativity of minute.
return 0;
}

Output:-

When you will choose the wrong choice initially.

When you enter the negative value of minute.

In the above program, I just code as the question says.