C++ If ... Else Examples
Real Life Example
This example shows how you can use if..else to "open a door" if the user enters the correct code:
Example
int doorCode = 1337;
if (doorCode == 1337) {
cout << "Correct
code.\nThe door is now open.\n";
} else {
cout << "Wrong
code.\nThe door remains closed.\n";
}
Try it Yourself »
This example shows how you can use if..else to find out if a number is positive or negative:
Example
int myNum = 10; // Is this a positive or negative number?
if (myNum >
0) {
cout << "The value is a positive number.\n";
} else if
(myNum < 0) {
cout << "The value is a negative number.\n";
} else
{
cout << "The value is 0.\n";
}
Try it Yourself »
Find out if a person is old enough to vote:
Example
int myAge = 25;
int votingAge = 18;
if (myAge >= votingAge) {
cout << "Old enough to vote!\n";
} else {
cout << "Not old enough
to vote.\n";
}
Try it Yourself »
Find out if a person is old enough to vote, and if they are a citizen (using nested if statements):
Example
int age = 20;
bool isCitizen = true;
if (age >= 18) {
cout << "Old enough to vote.\n";
if (isCitizen) {
cout << "And you are a citizen, so you can vote!\n";
} else {
cout << "But you must be a citizen to vote.\n";
}
} else {
cout << "Not old enough to vote.\n";
}
Find out if a number is even or odd:
Example
int myNum = 5;
if (myNum % 2 == 0) {
cout << myNum << " is
even.\n";
} else {
cout << myNum << " is odd.\n";
}
Try it Yourself »
Check temperature (Celsius):
Example
int temperature = 30;
if (temperature < 0) {
cout << "It's freezing!\n";
} else if (temperature < 20) {
cout << "It's cool.\n";
} else {
cout << "It's warm.\n";
}