How can I end a do-while cycle? - c++

Question

Im new at programming and for homework, my teacher ask me to make an option menu that does different things, but I have a problem, case 5 is supposed to end the program, but if I select 5, the do-while cycle keeps asking me if I want to do something else, when I need that if I choose 5, the program ends, how can I end with the cycle and put the option to exit the program?
Thanks, and any help is welcome
#include <iostream>
#include <stdio.h>
#include <time.h>
#include <conio.h>
using namespace std;
int main() {
string name, lname;
int an, result;
int num;
char option;
int n, x;
time_t t, b;
char* f;
int flag = 0;
int i = 0;
do {
cout << "Option Menu";
cout << "\n1) Name and your last name";
cout << "\n2) Years of life";
cout << "\n3) First 100 numbers divisible by 3";
cout << "\n4) Date and hour";
cout << "\n5) Exit\n";
cin >> num;
switch (num) {
case 1:
cout << "\nWrite your name: ";
cin >> name;
cout << "\nWrite your last name: ";
cin >> lname;
cout << "\nYour complete name is: " << name << " " << lname;
break;
case 2:
cout << "\nWhat year you were born?: ";
cin >> an;
result = 2019 - an;
cout << "\nYou have " << result << " years\n";
break;
case 3:
for (i = 0; flag < 100; i++) {
if (i % 3 == 0) {
cout << i << "\n";
flag++;
}
}
break;
case 4:
b = time(&t);
f = ctime(&b);
printf("%s\n", f);
getch();
break;
}
cout << "\n Do you want to do something else?: ";
cin >> option;
} while (option == 's' or option == 'S');
cout << "\nGood bye :)" << endl;
system("pause");
return 0;
}

Answer 1

It's probably easiest to just simply use the if statement to check if num == 5 outside the switch statement and break the while loop when num is equal to 5.
#include <iostream>
#include <stdio.h>
#include <time.h>
#include <conio.h>
using namespace std;
int main() {
string name, lname;
int an, result;
int num;
char option;
int n, x;
time_t t, b;
char* f;
int flag = 0;
int i = 0;
do {
cout << "Option Menu";
cout << "\n1) Name and your last name";
cout << "\n2) Years of life";
cout << "\n3) First 100 numbers divisible by 3";
cout << "\n4) Date and hour";
cout << "\n5) Exit\n";
cin >> num;
switch (num) {
case 1:
cout << "\nWrite your name: ";
cin >> name;
cout << "\nWrite your last name: ";
cin >> lname;
cout << "\nYour complete name is: " << name << " " << lname;
break;
case 2:
cout << "\nWhat year you were born?: ";
cin >> an;
result = 2019 - an;
cout << "\nYou have " << result << " years\n";
break;
case 3:
for (i = 0; flag < 100; i++) {
if (i % 3 == 0) {
cout << i << "\n";
flag++;
}
}
break;
case 4:
b = time(&t);
f = ctime(&b);
printf("%s\n", f);
getch();
break;
}
if (num == 5) {
break;
}
cout << "\n Do you want to do something else?: ";
cin >> option;
} while (option == 's' || option == 'S');
cout << "\nGood bye :)" << endl;
system("pause");
return 0;
}

Answer 2

To accomplish this task, your switch must have either a case 5: or a default: block which assigns a value other than s or S to the option variable. That will allow your program to break out of the do..while loop.
There is another problem though. The user will still be asked if he wants to do something else even if they chose the Exit option. To avoid this, you can use an extra variable (for example, a userExits boolean) to skip the part where the program asks for input after the switch.
Here is a possible solution:
// after all the variable declarations
bool userExits = false;
do {
// All menu options
cin >> num;
switch (num) {
// (...)
case 4:
b = time(&t);
f = ctime(&b);
printf("%s\n", f);
getch();
break;
case 5:
userExits = true;
break;
}
if (userExits){
option = "exit";
}
else{
cout << "\n Do you want to do something else?: ";
cin >> option;
}
} while (option == 's' or option == 'S');
cout << "\nGood bye :)" << endl;