If statement in C++ - Step-by-Step Execution

Concept Flow - If statement

Start

↓

Evaluate condition

↓

Execute if-block

↓

Continue

↓

Skip if-block

↓

Continue

The program checks a condition. If true, it runs the code inside the if-block; if false, it skips it and continues.

Execution Sample

C++

#include <iostream>
using namespace std;

int main() {
    int x = 5;
    if (x > 3) {
        cout << "x is greater than 3" << endl;
    }
    cout << "Done" << endl;
    return 0;
}

Checks if x is greater than 3, prints a message if true, then prints "Done".

Execution Table

Step	Condition (x > 3)	Result	Branch Taken	Output
1	5 > 3	True	Execute if-block	x is greater than 3
2	N/A	N/A	Continue after if	Done

💡 After executing the if-block, program continues to print "Done" and ends.

Variable Tracker

Variable	Start	After Step 1	After Step 2
x	5	5	5

Key Moments - 2 Insights

Why does the program print "x is greater than 3"?

Because the condition x > 3 is true at step 1, so the if-block runs and prints the message.

What happens if the condition is false?

The program skips the if-block and directly continues to the next statement, as shown in step 2.

Visual Quiz - 3 Questions

Look at the execution table, what is the condition result at step 1?

A False

B True

C Undefined

D Zero

💡 Hint

Check the 'Condition (x > 3)' column at step 1 in the execution table.

At which step does the program print "Done"?

A Step 1

B Before step 1

C Step 2

D Never

💡 Hint

Look at the 'Output' column in the execution table for when "Done" is printed.

If x was 2 instead of 5, what would happen at step 1?

A Condition false, if-block skipped

B Program crashes

C Condition true, if-block runs

D Output prints twice

💡 Hint

Refer to the condition x > 3 and what happens when it is false in the key moments.

Concept Snapshot

If statement syntax:
if (condition) {
    // code runs if condition true
}

Checks condition once.
Runs block only if true.
Skips block if false.
Then continues program.

Full Transcript

This visual trace shows how an if statement works in C++. The program starts by evaluating the condition x > 3. Since x is 5, the condition is true, so the code inside the if-block runs and prints "x is greater than 3". Then the program continues and prints "Done". If the condition were false, the if-block would be skipped and only "Done" would print. Variables remain unchanged during this process.