1. #include <bits/stdc++.h>
2. using namespace std;
3.  
4. vector<string> menu_items= {
5.  "New", "Withdrawal", "Deposit", "Check Balance", "Display All", "Fund Transfer", "Exit"
6. };
7. const int EXIT_CODE = menu_items.size();
8.  
9. typedef struct {
10.  int id;
11.  string name;
12.  float balance;
13. } MyAccount;
14.  
15. map<int, MyAccount> accounts;
16.  
17.  
18. void add();
19. void withdraw(){};
20. void deposite(){};
21. void checkBalance();
22. void displayAll();
23. void fundTransfer();
24. void loadDataTable();
25.  
26. int ran = 0;
27.  
28. int menu() {
29.  
30.  if (ran == 0) {
31.   loadDataTable();
32.   ++ran;
33.  }
34.  
35.  int op = 0;
36.  int items = menu_items.size();
37.  
38.  cout << "<----- MENU -----&gt;\n";
39.  for (int i = 0; i < items; i++) {
40.   cout << '\t' << i+1 << ". " << menu_items[i] << '\n';
41.  }
42.  
43.  printf("Enter your choice (1-%d): ", items);
44.  cin >> op;
45.  
46.  if ( !(op >= 1 && op <= items) ) {
47.   cout << "Invalid Choice! Please select again!\n";
48.   menu();
49.  }
50.  
51.  return op;
52. }
53.  
54. int main() {
55.  
56.  int op = menu();
57.  
58.  if (op == EXIT_CODE) {
59.   cout << "<----- Program Exit -----&gt;\n";
60.   return 0;
61.  }
62.  
63.  cout << "\n\n\t<----- " << menu_items[op-1] << " -----&gt;\n";
64.  switch (op) {
65.   case 1: add(); break;
66.   case 2: withdraw(); break;
67.   case 3: deposite(); break;
68.   case 4: checkBalance(); break;
69.   case 5: displayAll(); break;
70.  }
71.  
72.  main();
73.  return 0;
74. }
75.  
76.  
77. void add() {
78.  
79.  MyAccount ac;
80.  
81.  while(true) {
82.   cout << "Enter your account ID: ";
83.   cin >> ac.id;
84.  
85.   if (accounts.find(ac.id) == accounts.end()) break;
86.  
87.   cout << "This account already exists! Enter a different ID.\n";
88.  }
89.  
90.  cout << "Enter your name: ";
91.  cin >> ac.name;
92.  
93.  cout << "Enter your deposite amount: ";
94.  cin >> ac.balance;
95.  
96.  accounts[ac.id] = ac;
97.  
98.  cout << "\n\t\tAccount creation successful!\n";
99.  return;
100.  
101. }
102.  
103. void checkBalance() {
104.  cout << "Enter your account ID: ";
105.  
106.  int id;
107.  cin >> id;
108.  
109.  if (accounts.find(id) == accounts.end()) {
110.   cout << "Account not found!\n\n";
111.   return;
112.  }
113.  
114.  cout << "\n\n\tOwner name: " << accounts[id].name << '\n';
115.  cout << "\tBalance: " << accounts[id].balance << '\n';
116.  cout << "\n\n";
117.  
118. }
119.  
120. void displayAll() {
121.  for (auto ac: accounts) {
122.   cout << "\n\n\tAccount ID: " << ac.second.id << '\n';
123.   cout << "\tAccount Owner Name: " << ac.second.name << '\n';
124.   cout << "\tBalance: " << ac.second.balance << '\n';
125.  }
126.  
127.  cout << "\n\n";
128. }
129.  
130. void fundTransfer() {
131.  // validify sender and receiver accounts.
132. }
133.  
134. void loadDataTable() {
135.  
136.  ifstream file&#40;"accounts.txt"&#41;;
137.  
138.  while(!file.eof()) {
139.   MyAccount ac;
140.   file >> ac.id >> ac.name >> ac.balance;
141.   accounts[ac.id] = ac;
142.  }
143. }
144.