Loops

gistfile1.java

// For loops are a simple way to count numbers in a pattern. In this case the pattern is that all numbers
// increase by one each cycle through the loop. The first cycle will start with the variable i (which
// is an integer (a number, but not a fraction)) as the number 0. Then the next cycle, it's 1, then 2 ...
// All the way until the last cycle where it's 9, then when you add by 1 and make i = 10

for (Assign local seed value; exit conditional; increment or modify the variable) {
    System.out.println(i);
}

// The whole time, whenever the cycle forced us to increment the number (+1), then it was also checking the
// exit conditional (i < 10). When i = 1, it checked to make sure (1 < 10), which was a true statement.

// At the point where i = 10, the exit conditional (i < 10) would be shown as (10 < 10). A statement which
// is false. Since the exit conditional is false, it exits the loop.
for (int i = 0; i < 10; i++) {
    System.out.println(i);
}



// While loops are more customizable, but more dangerous if you don't know what your doing. As you can make
// infinite loops really easily.

while (true) {}

// There is one main difference from the for loop, it will check the exit condition (the part inside the
// brackets) first before cycling though the loop.


int i = 0; // We need to make the counter variable ourselves.
while (true) {
    System.out.println(i);

    // We need to increment the counter ourselves
    i += 1;
    if (i >= 10) { // We need to check the exit conditional ourselves. When this statement is true ...
        break; // Exit the loop
    }
}


int i = 0;
// We could also move the conditional here. However we must have the condition be a true
// statement for it to run, and then become a false statement for it to exit.
while (i < 10) {
    System.out.println(i);

    i += 1;
}