Menu driven project - c++

Question

The instructor want us to write a program that can re displays the menu only when the user wants to restart a selection and add an option to continue with another selection.
The problem I have is when the user select a number from 1 to 4 and complete the selection, the program will ask the user if the user want to continue with another selection and when the user says no, the program still ask to select a number without ending program.
here is my code that I've written so far:
#include<iostream>
using namespace std;
int sp;
int speed = 0;
int M, K, c, x;
const int MINspeed = 10;
const int MAXspeed = 40;
int GetSpeed();
int GetMinSpeed();
int GetMaxSpeed();
int CheckContinue();
int selection;
int GetSpeed()
{
char c;
while(true)
{
cout << "\nDo you want the speed in mph or km/h? \n"
<< "\nEnter M or K followed by Enter: " << endl;
cin >> c;
if( (c != 'M')&& (c != 'K'))
{
cout << "Incorrect Selection. Try Again! \n\n";
break;
}
if ( c == 'M')
{
cout << "\nSpeed in mph: " << speed << endl;
return speed;
}
else if(c == 'K')
{
double toKmPerHour = 1.61;
double speedInKmPerHour = speed * toKmPerHour;
cout << "\nSpeed in km/h:" << speedInKmPerHour << endl;
break;
}
CheckContinue();
}
return 0;
}
int GetMinSpeed()
{
cout << "MIN speed = " << MINspeed << endl;
CheckContinue();
return 0;
}
int GetMaxSpeed()
{
cout << "MAX speed = " << MAXspeed << endl;
CheckContinue();
return 0;
}
/*int SetSpeed(int sp)
{
cout << "The Set Speed is " << sp << endl;
return 0;
}
*/
void SetSpeed()
{
cout << "Input your speed: ";
cin >> speed;
CheckContinue();
}
int CheckContinue(void)
{
char x;
while(true)
{
cout << "\nDo you want to continue with another selection? \n"
<< "\nEnter Y or N followed by Enter: " << endl;
cin >> x;
if ( x == 'Y')
{
int selection;
cout << "Selection Menu" << endl;
cout << "--------------" << endl;
cout << "\n1. Set Speed" << endl;
cout << "2. Get Speed" << endl;
cout << "3. Get MAX Speed" << endl;
cout << "4. Get MIN Speed" << endl;
cout << "5. Exit" << endl;
cout << "\nYour selection :" <<endl;
cin >> selection;
switch(selection)
{
case 1:
SetSpeed();
break;
case 2:
GetSpeed();
break;
case 3:
GetMaxSpeed();
break;
case 4:
GetMinSpeed();
break;
case 5:
cout << "Good Bye" << endl;
break;
}
}
else if(x == 'N')
{
break;
}
}
return 0;
}
/*
In this menu function, it will ask the user to input the selection, ranging from 1 to 5.
If the user puts a number that is not between 1 to 5 or letters, then the program will
ask the user to input a valid selection.
*/
void menu()
{
int selection;
cout << "Selection Menu" << endl;
cout << "--------------" << endl;
cout << "\n1. Set Speed" << endl;
cout << "2. Get Speed" << endl;
cout << "3. Get MAX Speed" << endl;
cout << "4. Get MIN Speed" << endl;
cout << "5. Exit" << endl;
int bye = 0;
while(1)
{
cout << "\nYour selection :" <<endl;
cin >> selection;
bye = 0;
if((selection <= 5)&&(selection >= 1))
{
switch(selection)
{
case 1:
SetSpeed();
break;
case 2:
GetSpeed();
break;
case 3:
GetMaxSpeed();
break;
case 4:
GetMinSpeed();
break;
case 5:
cout << "Good Bye" << endl;
bye = -1;
break;
}
}
else
{
cout << "\nPlease input valid selection: " << endl;
cin >> selection;
switch(selection)
{
case 1:
SetSpeed();
break;
case 2:
GetSpeed();
break;
case 3:
GetMaxSpeed();
break;
case 4:
GetMinSpeed();
break;
case 5:
cout << "Good Bye" << endl;
bye = -1;
break;
}
}
if(bye == -1)
{
break;
}
}
}
int main()
{
menu();
return 0;
}//end of main function

Answer 1

This might serve your purpose. Call ask() as per your requirement if it didn't suit you.
#include <iostream>
#include <stdlib.h>
using namespace std;
char * title;
int a , b;
void menu();
void print(const char *c , int res )
{
cout<<"\n\n\n\n\nThe "<<c<<" of "<<a<<" and "<<b<<" is : " <<res<<endl;
}
void add()
{
print("Addition" , (a+b));
}
void sub()
{
print("subtraction" , (a-b));
}
void mul()
{
print("Multiplication" , (a*b));
}
void div()
{
print("Division" , (a/b));
}
void ask()
{
bool call_menu;
char ch;
cout<<"\n\n\n\n\n\n DO you Want to Continue? Y - N: ";
cin>>ch;
if(ch=='Y' || ch=='y')
{
call_menu= true;
}
else
{
if(ch=='N' || ch == 'n')
{
call_menu= false;
}
else
{
cin.clear();
ask();
}
}
if(call_menu)
{
system("clear"); // change this to system("cls") if on windows
menu();
}
else
{
system("clear"); // change this to system("cls") if on windows
cout<<"\n\n\n\n\n\n\n\t\t\tHave a Nice Day ! \n\n\n"<<endl;
}
}
void input(int *first , int *second)
{
system("clear"); // change this to system("cls") if on windows
cout<<"\n\n\n\t\t\t\t Calculator \n\n\n\n"<<endl;
cout<<"Enter the First Number : ";
cin>>(*first);
cout<<"\nEnter the Second Number :";
cin>>(*second);
}
void menu()
{
int ch;
cout<<"\n\n\n\t\t\t\t Calculator \n\n\n\n"<<endl;
cout<<"\n\n\t\t\t1 . Addition"<<endl;
cout<<"\n\n\t\t\t2 . Subtract"<<endl;
cout<<"\n\n\t\t\t3 . Multiply"<<endl;
cout<<"\n\n\t\t\t4 . Division"<<endl;
cout<<"\n\n\t\t\t5 . Exit" <<endl;
cout<<"\n\n\n\n Enter Your Choice : ";
cin>>ch;
if(ch >=1 && ch <5){
input(&a , &b);
}
switch(ch)
{
case 1:
add();
ask();
break;
case 2:
sub();
ask();
break;
case 3:
mul();
ask();
break;
case 4:
div();
ask();
break;
case 5:
exit(0);
break;
default:
system("clear"); // change this to system("cls") if on windows
cin.clear();
cin.ignore();
menu();
break;
}
}
int main(int argc, char **argv)
{
menu();
return 0;
}
Modify it as per your requirement.

Answer 2

There are several problems with the code in your question. The big problem is there is a lot of redundant code that can be easily eliminated by a few minor adjustments. You have both the menu printing and code to act on selections in several places. This is going to make managing the continue process a lot more difficult. By eliminating the redundant code and adjusting the logic in main and and menu you can not only reduce the complexity but make it far easier to manage.
For instance menu can be changed to remove the while loop and return a boolean value to indicate if the user wants to exit. This will allow you to select an option, act on it, then return letting other portions of the program handle asking the user if they want to continue.
The example below is a modification of your original code. It only addresses the logic for asking the user to continue and eliminates the redundant menu code. You should review the entire code and make additional adjustments as necessary.
#include <iostream>
#include <string>
using namespace std;
int sp;
int speed = 0;
int M, K, c, x;
const int MINspeed = 10;
const int MAXspeed = 40;
int GetSpeed()
{
char c;
while(true)
{
cout << "\nDo you want the speed in mph or km/h? \n"
<< "\nEnter M or K followed by Enter: " << flush;
cin >> c;
if( (c != 'M')&& (c != 'K'))
{
cout << "Incorrect Selection. Try Again! \n\n" << flush;
continue;
}
if ( c == 'M')
{
cout << "\nSpeed in mph: " << speed << endl;
return speed;
}
else if(c == 'K')
{
double toKmPerHour = 1.61;
double speedInKmPerHour = speed * toKmPerHour;
cout << "\nSpeed in km/h:" << speedInKmPerHour << endl;
return speed;
}
}
return 0;
}
int GetMinSpeed()
{
cout << "MIN speed = " << MINspeed << endl;
return 0;
}
int GetMaxSpeed()
{
cout << "MAX speed = " << MAXspeed << endl;
return 0;
}
void SetSpeed()
{
cout << "Input your speed: ";
cin >> speed;
}
/*
In this menu function, it will ask the user to input the selection, ranging from 1 to 5.
If the user puts a number that is not between 1 to 5 or letters, then the program will
ask the user to input a valid selection.
returns false if the user has selected the exit option
returns true for all other options
*/
bool menu()
{
cout << "Selection Menu" << endl;
cout << "--------------" << endl;
cout << "\n1. Set Speed" << endl;
cout << "2. Get Speed" << endl;
cout << "3. Get MAX Speed" << endl;
cout << "4. Get MIN Speed" << endl;
cout << "5. Exit" << endl;
int selection;
cout << "\nYour selection :" <<endl;
cin >> selection;
switch(selection)
{
case 1:
SetSpeed();
break;
case 2:
GetSpeed();
break;
case 3:
GetMaxSpeed();
break;
case 4:
GetMinSpeed();
break;
case 5:
cout << "Good Bye" << endl;
return false;
break;
default:
cout << "\nPlease input valid selection: " << endl;
}
return true;
}
int main()
{
for(bool process = true; process;)
{
process = menu();
if(process)
{
for(bool valid = false; !valid;)
{
cout << "\nDo you want to enter another selection? (Yes/No) " << flush;
cin.clear();
cin.ignore(numeric_limits<streamsize>::max(), '\n');
string line;
getline(cin, line);
if(line == "No")
{
valid = true;
process = false;
}
else if(line == "Yes")
{
valid = true;
}
else
{
cout << "\nInvalid input\n\n" << flush;
}
}
}
}
return 0;
}//end of main function