If Control Structure-- I'm stuck again!

Question

Woe is me.. stuck again. Below is a snippit of my code. The two middle "if's" won't compile properly because apparently there is/are ")" missing. No matter where I put the missing ")" it still won't work. Obviously I am not writing this out correctly but can't find anything to tell me how to go about joining up > "AND" = . Can anyone help?
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if(area <10) //Areal is less than 10.
     System.out.println("This is a tiny area");
if(area 10>=30) //Areal is between 10 & 30 inclusive.
     System.out.println("This is a small area");
if(area 30>=100) // Area is between 30 & 100 inclusive.
     System.out.println("This is a large area");
if(area >30) //Area is greater than 100.
     System.out.println("This is a huge area");
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Answer 1

More food....
check this out:
if(area < 10) { // area is less than 10.
System.out.println("This is a tiny area");
else { // area is greater than 9
if(area <= 30) {
System.out.println("This is a small area");
else { // area is greater than 30
if(area <= 100) {
System.out.println("This is a large area");
else { // area is greater than 100
System.out.println("This is a huge area");
Take care when creating such constructs.
Note: Your tests on the value range of area are exclusive, meaning only one of the tests ("if statements" can be true in the above example). But sometimes you'll need to make tests on overlapping ranges. The question then arises if the you want to proceed after a first sucessful test:
if(area > 5) {
System.out.println("Area is greater than 5.");
if(area > 10) {
System.out.println("Area is greater than 10.");
if area was 20 in the example, both test would be successful. Now what if you would change the value of "area" depending on the test?
if(area > 5) // test 1 {
System.out.println("Area is greater than 5.");
area = area + 7;
if(area > 10) // test 2 {
System.out.println("Area is greater than 10.");
Now, if area originally had a value of 6, test 1 would be sucessful, test 2 would not - if you hadn't modified area's value in test 1.
Therefore, always think about what exactly you want to test, and how you want to treat a sequence of tests. You can use either "else" branches to achieve this or use the "break" statement.
TIP: Sketch a reverse tree on a paper:
O
O O
O O O O
Now, each "O" is actually a test. Each "\" is the stuff you do when that test was sucessfull, each "/" the stuff when it was NOT sucessful, usually the "else" branch of an if statement:
if(test) {
// successful
else {
// not sucessful
1. Always be careful when creating such if-else contstructs, especially when you modify the tested value. Write it down using a tree as suggested.
2. Never modify the tested value inside of if-else constructs. :)
...ah, the phone rings, I was just starting .... :)
Patrick