Do- While loop

This loop can be used for executing the statements multiple times. A do-while loop has to be used when we do not know the exact number of iterations.

Syntax:

do{
   statements;
 }
while(condition);

Program 8:

class DoWhileDemo{
   public static void main(String args[]){
      int n=9,i=1;
      do{
      System.out.println(n+"*"+i+=+(n*i)));
      i++;
      } while (i<=10);
   }
}

Rule1: Specifying a condition to do-while loop is mandatory and it should be of boolean type.

Rule2: Specifying the { } is optional. If we do not specify the { } then we must specify exactly only one statement. If we want to consider multiple statements then specifying the { } is mandatory. Within the { } we can specify any number of statements.

Difference between while loop & do-while loop

1. In a while loop the statements will execute after evaluating the condition, whether in a do-while loop the statements will exexute before evaluating the condition.
2. In a while loop if the condition is false for the first time then the statement will not execute, whereas in a do-while loop if the first time then the statements will execute for one time.
3. In a while loop the statements will execute for 0 or more times, whereas in a do-while loop the statements will execute for 1 or more times.