Scala Loops

Types of Loops in Scala

Loop is used to execute the block of code several times according to the condition given in the loop. It means it executes the same code multiple times so it saves code and also helps to traverse the elements of the array.
There are 3 types of the loop –

• while loop
• do – while loop
• for loop

Watch this Spark-Scala video

while Loop –

While loop execute the code until condition is false.
Syntax

while(condition){
//code
}

e.g.

object Intellipaat {
def main(args: Array[String]) {
var I = 20;
while( a >10 ){
println( "Value of I is: " + I );
I = I - 2;
}
}
}

Compile and execute the above program:
scalac Intellipaat.scala
scala Intellipaat
Output
Value of I is:20
Value of I is:18
Value of I is:16
Value of I is:14
Value of I is:12

do – while loop

It also executes the code until the condition is false. In this at least once, code is executed whether the condition is true or false, but this is not the case with a while. While the loop is executed only when the condition is true.

 Syntax

do
{
//code
}while(condition);

e.g.

object Intellipaat {
def main(args: Array[String]) {
var I = 20;
do{
println( "Value of I is: " + I );
I = I - 2;
} while( a >10 );
}
}

Compile and execute the above program:
scalac Intellipaat.scala
scala Intellipaat
Output
Value of I is:20
Value of I is:18
Value of I is:16
Value of I is:14
Value of I is:12
Value of I is:10

for loop

It also executes the code until a condition is false. It is used when the number of iterations is known where while is used when the number of iterations is not known.

Syntax

for( var I <- Range ){
//code
}

e.g.

object Intellipaat {
def main(args: Array[String]) {
var I = 0;
for (I <- 1 to 10){
println( "Value of I is: " + I );
I = I + 2;
}
}
}

Compile and execute the above program:
scalac Intellipaat.scala
scala Intellipaat
Output
Value of I is:1
Value of I is:3
Value of I is:5
Value of I is:7
Value of I is:9