for loop

 

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Executes a loop.

Used as a more readable equivalent of while loop.

Syntax

for ( init_expression ; cond_expression ; iteration_expression ) loop_statement

Explanation

The above syntax produces code equivalent to:

{ init_expression ; while ( cond_exression ) { loop_statement iteration_expression ; } }

The init_expression is executed before the execution of the loop. The cond_expression shall evaluate to value, convertible to bool. It is evaluated before each iteration of the loop. The loop continues only if its value is true. The loop_statement is executed on each iteration, after which iteration_expression is executed.

If the execution of the loop needs to be terminated at some point, break statement can be used as terminating statement.

If the execution of the loop needs to be continued at the end of the loop body, continue statement can be used as shortcut.

Keywords

for

Example

#include <iostream>
 
int main() 
{
    for (int i = 0; i < 10; i++) {
        std::cout << i << " ";
    }
 
    std::cout << '\n';
 
    for (int j = 2; j < 9; j = j + 2) {
        std::cout << j << " ";
    }
}

Output:

0 1 2 3 4 5 6 7 8 9
2 4 6 8