How to display user account only using user ID num - c++

Question

Im basically making a database that stores a users account info. (Name, Phone number, ID, etc) I want to be able to display a specific persons info by entering in their ID num.
I have a struct with basic info and an array struct that stores each person and their info. I need to be able to type in a persons ID and have it display their info.
(I am still in first year of CS degree plz be gentle lol)
struct Account{
string name;
string city;
string state;
int ZIP;
int phone;
int IDNUM;
double ACT_BAL;
string LST_PMNT;};
Main fuction
const int SIZE = 20;
Account customers[SIZE];
const int NEW_INFO = 1, CHNG_INFO = 2, DISP = 3, EXIT = 4;
char choice1;
int choice;
int n;
int NEWCUST;
int results;
do
{ // menu display
cout << "Customer Database\n"
<< "----------------------------\n"
<< "1. Enter new account info\n"
<< "2. Change account info\n"
<< "3. Display all account info\n"
<< "4. Exit\n";
cin >> choice;
//respond to user input
switch (choice)
case NEW_INFO:
cout << "Would you like to enter a new cusomter?\n"
<< "(Y/N)";
cin >> choice1;
if (choice1 == 'Y' || choice1 == 'y')
{
cout << "How many new customers?" << endl; //User eneters in new customer info without having to enter in a full array worth of customers.
cin >> NEWCUST;
for (n = 0; n < NEWCUST; n++)
{
cout << "ID Number: ";
cin >> customers[n].IDNUM;
cout << "Enter in a name: ";
cin >> customers[n].name;
cout << "City: ";
cin >> customers[n].city;
cout << "State: ";
cin >> customers[n].state;
cout << "ZIP code: ";
cin >> customers[n].ZIP;
cout << "Phone number: ";
cin >> customers[n].phone;
cout << "Account Balance: ";
cin >> customers[n].ACT_BAL;
cout << "Lasy payment date: ";
cin >> customers[n].LST_PMNT;
}
}
break;
case CHNG_INFO: // Changes info
break; // displays all info (work in progress)
case DISP:
cout << "Enter customers ID number" << endl;
cin >> customers[].IDNUM;
results = linearSearch(customers, SIZE, customers[].IDNUM);
break;
case EXIT:
cout << "Cosing......" << endl; //exits progeam
break;

Answer 1

To get a specific user details, you can do the following:
Declaring num as short int to hold a simple User ID, you can change it. N = 50 as you've provided the constant. Now, unless the loop finds the inputted ID matching with one of the struct's idNum, it'll be executed 50 times (max).
cout << "Input account code: ";
cin >> num;
for (int i = 0; i < N; i++)
{
if (num == acc[i].idNum)
{
cout << "Name: " << acc[i].name << endl
<< "..." << endl;
}
}