C++ for Keyword
Example
Print the numbers 0 to 4:
for (int i = 0; i < 5; i++) {
cout << i << "\n";
}
Definition and Usage
The for loop loops through a block of code a number of times.
From the example above:
- Statement 1 sets a variable before the loop starts (int i = 0).
- Statement 2 defines the condition for the loop to run (i must be less than 5). If the condition is true, the loop will start over again, if it is false, the loop will end.
- Statement 3 increases a value (i++) each time the code block in the loop has been executed.
More Examples
There is also a "for-each loop" (introduced in C++ version 11 (2011)), which is used exclusively to loop through elements in an array (or other data sets):
The following example outputs all elements in an array, using a "for-each loop":
Example
int myNumbers[5] = {10, 20, 30, 40, 50};
for (int i : myNumbers) {
cout << i << "\n";
}
Related Pages
Read more about for loops in our C++ For Loop Tutorial.
