Program Crash When I try to Find a Number in List

[peasforbrains]

Everything in my code works except for the part when I try to find a number in the list. If I try to find a number that's not there when there's something in the list, the code works but it crashes and I'm not sure why. Please help! Thank you.

Here is my code:

#include<iostream>
#include<cstdlib>
#include<conio.h>

using namespace std;

struct Node
{
    Node *previous;
    int number;
    Node *next;
};

int main()
{
    Node *first = NULL;
    Node *last = NULL;
    Node *tempPrevious;
    Node *tempNext;
    Node *N;

    int inList;
    int option, temp;

    inList = 0;

    do
    {
        system("cls");
        cout << "Enter one of the following options: " << endl;
        cout << "\n\t1 - Display numbers in list ";
        cout << "\n\t2 - Add number to the front of the list ";
        cout << "\n\t3 - Add number to the end of the list ";
        cout << "\n\t4 - Find number in the list ";
        cout << "\n\t5 - Quit " << endl;
        cout << "\n\tEnter you option: " << flush;
        cin >> option;

        switch(option)
        {
            case 1:
                system("cls");
                if(inList == 0)
                {
                    cout << "List is empty. " << endl;
                }
                else
                {
                    cout << "List contains: " << endl;
                    N = first;
                    while(N -> next != NULL)
                    {
                        cout << N -> number << ", ";
                        N = N -> next;
                    }
                    cout << N -> number;
                    cout << " Null - End of List";
                }

                cout << "\nPress any key to continue. ";
                getch();
                break;

            case 2:
                system("cls");
                N = new Node;
                inList += 1;
                cout << "Enter number: " << flush;
                cin >> temp;
                N -> previous = NULL;
                N -> number = temp;
                N -> next = first;
                first = N;
                if(inList == 1)
                {
                    last = N;
                }
                if(inList > 1)
                {
                    N = N -> next;
                    N -> previous = first;
                }
                cout << "\nPress any key to continue. ";
                getch();
                break;

            case 3:
                system("cls");
                N = new Node;
                inList += 1;
                if(inList == 1)
                {
                    first = NULL;
                }
                cout << "Enter a Number: " << flush;
                cin >> temp;
                N -> previous = last;
                N -> number = temp;
                N -> next = NULL;
                last = N;
                if(first == NULL)
                {
                    first = N;
                    N -> previous = NULL;
                }
                else
                {
                    N = N -> previous;
                    N -> next = last;
                }
                cout << "\nPress any key to continue. ";
                getch();
                break;

            case 4:
                system("cls");

                if(inList == 0)
                {
                    cout << "List is empty. ";
                }
                else
                {
                    cout << "Enter number: " << flush;
                    cin >> temp;
                    N = first;

                    {
                        if(N -> number == temp)
                        {
                            cout << "\n" << temp << " is in the list. " << endl;
                            break;
                        }
                        else
                        {
                            tempPrevious = N -> previous;
                            tempNext = N -> next;
                            N = tempNext;
                        }
                        if(i = inList && N -> number != temp)
                        {
                            cout << "\n" << temp << " not in list." << endl;
                        }
                    }



                }
                cout << "\nPress any key to continue. ";
                getch();
                break;

            case 5:
                system("cls");
                cout << "Quitting... " << endl;
                exit(0);
                break;
        }

    }while(option != 5);
    return 0;
}

This is the part that doesn't work:

                       if(i = inList && N -> number != temp)
                        {
                            cout << "\n" << temp << " not in list." << endl;
                        }

Here is a photo with what happens when a number isn't on the list, it finds it but the exe crashes:
http://imgur.com/a/l0TYD

[boost lexical cast]

= is assignment operator and == is equality operator. It is easy to confuse these two. You should be using the == (equality) operator.