CSA Blog
Ian Wu
Unit 3 Team Teach - 3.4
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3.1: Boolean Expressions | 3.2: If Control Flow | 3.3: If Else | 3.4: Else If | 3.5: Compound Booleans | 3.6: Equivalent Booleans | 3.7: Comparing Objects | 3.8: Homework |
3.4 Else If Statements
Else If Statements: Used when you have multiple conditions that need to be checked sequentially.
Flow of Execution: Each condition is evaluated in the order written. The first true condition’s code runs, and the rest are skipped.
Structure:
- Start with a single if statement.
- Follow with as many else if statements as needed.
- Optionally end with one else to handle any remaining cases. Key Concept: The order of conditions matters. More specific conditions should come before broader ones to ensure accurate results.
- If I was 19 what would it print out?
- “Current age: 19”
- “You can register to vote.”
- “You are old enough for a license to drive.”
- If I was 13 what would it print out?
- “Current age: 13”
- Create your if statement with one else if condition.
boolean a = true;
boolean b = false;
boolean c = false;
if (!(a ^ b)) {
System.out.println("d");
} else if (c || b ^ a) {
System.out.println("e");
} else {
System.out.println("f");
}
e
Unit3_teamteach_3.3_ipynb_2_.md:zone
Unit 3 Team Teach - 3.3
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3.1: Boolean Expressions | 3.2: If Control Flow | 3.3: If Else | 3.4: Else If | 3.5: Compound Booleans | 3.6: Equivalent Booleans | 3.7: Comparing Objects | 3.8: Homework |
3.3 If Else Statements
Purpose of Else Statements
Else statements: Handles what happens when the if condition is false. Structure of If-Else:
- If statement with a condition.
- Else statement without a condition.
- Both parts have code blocks surrounded by {}.
don’t forget the brackets
if (x > 10) {
console.log("x is greater than 10");
console.log("This code when the condition is true");
} else {
console.log("x is 10 or less");
console.log("This code runs when the condition is false");
}
Without brackets:
if (x > 10)
console.log("x is greater than 10");
console.log("this code will always run");
| console.log("x is greater than 10");
illegal character: '\u00a0'
| console.log("x is greater than 10");
illegal character: '\u00a0'
| console.log("x is greater than 10");
illegal character: '\u00a0'
| console.log("x is greater than 10");
illegal character: '\u00a0'
| console.log("This code when the condition is true");
illegal character: '\u00a0'
| console.log("This code when the condition is true");
illegal character: '\u00a0'
| console.log("This code when the condition is true");
illegal character: '\u00a0'
| console.log("This code when the condition is true");
illegal character: '\u00a0'
| console.log("x is 10 or less");
illegal character: '\u00a0'
| console.log("x is 10 or less");
illegal character: '\u00a0'
| console.log("x is 10 or less");
illegal character: '\u00a0'
| console.log("x is 10 or less");
illegal character: '\u00a0'
| console.log("This code runs when the condition is false");
illegal character: '\u00a0'
| console.log("This code runs when the condition is false");
illegal character: '\u00a0'
| console.log("This code runs when the condition is false");
illegal character: '\u00a0'
| console.log("This code runs when the condition is false");
illegal character: '\u00a0'
- Based on this code, if you were younger than 16 what would it print out?
- “You are not old enough for a license yet”
- Write your own if else statement
boolean a = true;
boolean b = false;
boolean c = false;
if (a ^ b) {
System.out.println("d");
} else {
System.out.println("e");
}
d