help in c++

[unnameass]

how can i make this work . i want to enter the number Zero, but it is not working. i want to test if zero is positive or even and all. but when i enter 0 nothing happens

// Sundar Sekar

#include <iostream>

using namespace std;
// DEFINES

#ifndef __TRUE_FALSE__

#define __TRUE_FALSE__

#define TRUE 1

#define FALSE 0

#endif



// FUNCTION PROTOTYPES

int DisplayMenuSelections();
void SetTestNumber();
void SignTest();
void EvenOddTest();
void PrimalityTest();
int num;
int gTestNumber = 0;
bool gTestNumberSet = false;

int main() {

// loop till exit
while(gTestNumberSet == false) {
switch (gTestNumber) {
case 1:
SetTestNumber();
break;
case 2:
SignTest();
break;
case 3:
EvenOddTest();
break;
case 4:
PrimalityTest();
break;
case 5:
cout << "EXITING PROGRAM" << endl;
system("pause");
return 1;
break;
}

system("pause");
system("cls");
gTestNumber = DisplayMenuSelections();
}


return 0;
}
// FUNCTION IMPLEMENTATIONS
// returns the user's menu selection code
int DisplayMenuSelections() {
int gTestNumber;

//Initial Menu
cout << "+-------------------------------+" << endl;
cout << "$ NUMERICAL ANALYSIS ENGINE $" << endl;
cout << "+-------------------------------+" << endl;

cout << "The current test number is: ";
if(num==0) {
cout << "NOT YET SET" << endl << endl;
} else {
cout << num << endl << endl;
}

cout << "THE MENU" << endl;

//The default menu
cout << "1.) Set the test number." << endl;
if(num !=0) {
cout << "2.) Test for sign." << endl;
cout << "3.) Test for even/odd." << endl;
cout << "4.) Test for primality." << endl;
}
cout << "5.) Exit program" << endl;

// user will select from the menu
cout << endl << "Please input your selection from the menu above: ";
cin >> gTestNumber;

return (gTestNumber);
}
// set the number
void SetTestNumber() {
cout << "Enter the number would you like to test: ";
cin >> num;
}
// check for sign of the number
void SignTest() {
if(num > 0) {
cout << "The number is Positive" << endl;
}
if(num < 0) {
cout << "The number is Negative" << endl;

}
if (num==0) {
cout << "The number is NEUTRAL" << endl;

}
}
// check for even or odd
void EvenOddTest() {
int leftOvers = 1;
leftOvers = num % 2;
if(leftOvers == 0) {
cout << "The number is EVEN" << endl;
}
if (leftOvers != 0) {
cout << "The number is ODD" << endl;
}

}
// check for prime, composite
void PrimalityTest() {
int testA = 0;
int testB = 0;
bool prime = true;

if(num > 0) {
for(int i = 2; i < num; i++) {
testA = num % i;
testB = num / i;
if(testA == 0 && testB != num && testB != 1) {
prime = false;
}
}
if(prime == true) {
cout << "The number you have selected is PRIME" << endl;
}
if(prime == false) {
cout << "The number you have selected is COMPOSITE" << endl;
}
}
if(num <= 0) {
cout << "The number is neither PRIME or COMPOSITE" << endl;
}

}

[LB]

It looks like you have it set up to use 0 to mean that the number is not yet set.

[unnameass]

is it possible if you can show the code on how to set up. i want to enter the number 0 but nothing is happeneing

[Raman009]

I guess the problem is with your switch-case

int num;
cout << "Enter some number " << endl;
cin >> num ;
switch(num){
  case 0 : 
     cout << "You have entered zero " << endl;
     break;
  default :
    cout << "You have not entered zero ." << endl;
    cout << "The actual number is " << num; 
}

In your program ,nothing will execute if you have not defined the case for zero.
Always surround your code with <code> tags so that your code is readable.
Peace