Do While
layout: default
title: do-while Loops
The do-while loop is similar to the while loop, except the condition is placed after the loop body.
do
loop body
while (condition);
do-while loop body will always execute at least once.
int num = 0;
do {
System.out.println("num is " + num);
num = num + 1;
} while (num < 5);
Practice Exercise¶
Notable do-while differences:
* do-while must have a semicolon at the end.
* do-while will execute at least once.
int num = 999;
do {
System.out.println("num is " + num); //will execute even though num is not 0
} while (num == 0);
Drill¶
Note: these are similar to the while loop drills, but do not copy-paste solutions. The purpose here is to practice writing the code.
WhileLoops/src/drills/DoWhileLoop.java
* Write a do-while loop to print the numbers 1 to 10 to the screen.
* Use Math.random() to write a do-while loop that will execute as long as a random number is less than 0.7. Declare a variable outside the loop, and assign a new Math.random() value in the loop body. Then print the number to the screen. Example: double d = Math.random();
Add a statement after the loop to print the final value of d.