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Sample Fragments using the for loop

// Counting from 10 to 50 in increments (steps) of 5:

int x;

for ( x=10; x<=50; x= x+5 )              //**increment/decrement won't work here.
{                                                         // x = x + 5 is same as x += 5
     System.out.println("Loop counter value is " +  x );
}

 


//Counting from 50 to10 backwards in increments of 5:

int x;

for ( x=50; x>=10; x=x-5 )                       // x = x - 5 is same as x -=5
{
     System.out.println("Loop counter value is " + x);
}

 



// Declaring and assigning the startExpression within the for loop:

//Counting down from 10 to Blast Off
for ( int i = 10; i>= 1; i-- )               // notice the int
{
     System.out.println( i );
}
System.out.println("Blast off!");

 

// Keeping track of a "total" of values using a for loop:

int total = 0;            // must be initialized before the loop (avoid "garbage")

for (int count = 5; count <=10; count++ )
{
     total += count;
}
System.out.println("The total is " + total);



// The body of the loop may contain statements that further check on data: 

for (int ctr = 1; ctr <= 35; ctr++)            // will address 35 children
{
     child = Console.readLine("Enter the child's name: ");
     age = Console.readInt("Enter the child's age: ");

     if ((age >= 6) && (age <=7))
     {
          System.out.println(child + " has Mr. Escalante for a teacher.");
     }
     else
     {
           System.out.println(child + " does not have Mr. Escalante for a teacher.");
     }
}                     // Quits after 35 times.

 

// User determines length of for loop:

num = Console.readInt("How many stars shall I print?");
System.out.println("OK! Here I go .... ");

for (i = 1; i <= num; i++)
{
     System.out.print( * + " ");
}

 

// Titles and for loops:

//print titles OUTSIDE the loop to prevent multiple copies of the title
//print even numbers from 1 to 20 with title

System.out.println("Even numbers from 1 to 20 ");           //title is outside loop

for (int num = 2; num <= 20; num += 2)            //notice startExpression
{
     System.out.print( num + " ") ;                                     //prints the even numbers
}
 


                     
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