Arithmetic operators in C++ - Step-by-Step Execution

Concept Flow - Arithmetic operators

Start

↓

Read operands

↓

Choose operator: +, -, *, /, %

↓

Perform calculation

↓

Store/Display result

↓

End

The program starts by reading two numbers, then chooses an arithmetic operator to perform the calculation, and finally shows the result.

Execution Sample

C++

int a = 10;
int b = 3;
int sum = a + b;
int diff = a - b;
int prod = a * b;
int quot = a / b;
int mod = a % b;

This code calculates sum, difference, product, quotient, and remainder of two integers.

Execution Table

Step	Operation	Operands	Result	Explanation
1	Addition	10 + 3	13	Adds a and b, stores in sum
2	Subtraction	10 - 3	7	Subtracts b from a, stores in diff
3	Multiplication	10 * 3	30	Multiplies a and b, stores in prod
4	Division	10 / 3	3	Divides a by b (integer division), stores in quot
5	Modulo	10 % 3	1	Remainder of a divided by b, stores in mod
6	End	-	-	All operations done

💡 All arithmetic operations completed and results stored.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 4	After Step 5
a	10	10	10	10	10	10
b	3	3	3	3	3	3
sum	undefined	13	13	13	13	13
diff	undefined	undefined	7	7	7	7
prod	undefined	undefined	undefined	30	30	30
quot	undefined	undefined	undefined	undefined	3	3
mod	undefined	undefined	undefined	undefined	undefined	1

Key Moments - 3 Insights

Why does division 10 / 3 give 3 instead of 3.333?

Because both a and b are integers, C++ does integer division which discards the decimal part. See step 4 in execution_table.

What does the modulo operator (%) do?

It gives the remainder after division. For 10 % 3, the remainder is 1 as shown in step 5.

Are the original variables a and b changed by these operations?

No, a and b keep their original values throughout, only new variables store results. See variable_tracker.

Visual Quiz - 3 Questions

Look at the execution_table, what is the result of the multiplication at step 3?

A 30

B 13

C 7

D 3

💡 Hint

Check the 'Result' column for step 3 in execution_table.

At which step does the modulo operation happen?

A Step 2

B Step 5

C Step 4

D Step 1

💡 Hint

Look for '%' operator in the 'Operation' column in execution_table.

If variable b was 4 instead of 3, what would be the new result of 10 % b?

A 1

B 0

C 2

D 3

💡 Hint

Modulo gives remainder: 10 divided by 4 leaves remainder 2.

Concept Snapshot

Arithmetic operators in C++:
+ addition
- subtraction
* multiplication
/ division (integer if both operands int)
% modulo (remainder)
Operands must be numbers; integer division truncates decimals.

Full Transcript

This example shows how arithmetic operators work in C++. We start with two integers a=10 and b=3. We add them to get 13, subtract to get 7, multiply to get 30, divide to get 3 (integer division), and find remainder 1 using modulo. Variables a and b remain unchanged. Each step performs one operation and stores the result in a new variable. Integer division discards decimals. Modulo gives the remainder after division.