Java Basics - Loops 1

While Loops

 While loops are continuous loops that repeat as long as a condition stays true.

For Example:

while(x<5){
//execute some code here
x++:
}


_______________________________

For Loops

 for(int i=1; i<5; i++)
{
//write code here
}

Section 1: Intialize loop counter at value;

Section 2:  The condition to continue looping

Section 3: What to to the loop counter every cycle

Now.

Lets run through the following for loop below

for(int i=1; i<=5; i++)
{
//run code here
}

i
Is i<=5?
Step into loop again?
1
1<=5 (true)
Yes
2
2<=5 (true)
Yes
3
3<=5 (true)
Yes
4
4<=5 (true)
Yes
5
5<=5 (true)
Yes
6
6<=5 (false)
No

Note we only increment at the end of the loop.

for(int i=1; i<=5; i++)
{
//run code here
//increment i by 1 here at the end of the loop here.
}
__________________________________


Short notes on incrementing etc.

i=i-1  is the same as i--;
i=i+1 is the same as i++;
i=i+5 is the same as i +=5
i=i-6 is the same as i -=6
i=i*3 is the same as i*=3
i= i/2 is the same as  i/=2

__________________________________

Ending the loop before it reaches its conditions

To do this we can use the word break;

__________________________________






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