Demonstrate Assignment Operators in Java
beginner· Basics & I/O · Operators
Problem
Compound assignment operators (+= -= *= /= %=) combine an arithmetic operation with an assignment in one step, updating a variable in place instead of writing it out as a separate operation and reassignment.
Starting from a single variable, apply each compound assignment operator in sequence and print the running value after each step.
Input
10
Output
Start: 10
Java Program
Java
public class DemonstrateAssignmentOperators {
public static void main(String[] args) {
int value = 10; // simple assignment
System.out.println("Start: " + value);
value += 5; // same as value = value + 5
System.out.println("After += 5: " + value);
value -= 3; // same as value = value - 3
System.out.println("After -= 3: " + value);
value *= 2; // same as value = value * 2
System.out.println("After *= 2: " + value);
value /= 4; // same as value = value / 4
System.out.println("After /= 4: " + value);
value %= 4; // same as value = value % 4
System.out.println("After %= 4: " + value);
}
}Output
Start: 10
After += 5: 15
After -= 3: 12
After *= 2: 24
After /= 4: 6
After %= 4: 2
Core Logic
Each compound operator updates the same variable in place, so the running value from one step becomes the starting point for the next.
How It Works
- 1
int value = 10;uses the plain=operator to assign the starting value. - 2
value += 5;is shorthand forvalue = value + 5;, updatingvalueto15. - 3
value -= 3;,value *= 2;,value /= 4;, andvalue %= 4;each apply the same shorthand pattern for subtraction, multiplication, division, and modulo. - 4Because every step mutates the same variable, each operator's result depends on the value the previous operator left behind.
Starting from
10: += 5 gives 15, -= 3 gives 12, *= 2 gives 24, /= 4 gives 6, and %= 4 gives 2.💡
Key Point: value += 5 isn't just shorter than value = value + 5 — for narrower types like byte or short, the compound form also does an implicit cast the long form would need written out explicitly.
Key Concepts
= operator+= operator-= operator*= operator/= operator%= operator