🤔 Why is conditional and looping statements important??

Conditionals enable decision-making — programs can choose different actions based on input or situations (e.g., if user is logged in, show dashboard).
Loops enable repetition — they allow running the same block of code multiple times without rewriting it (e.g., processing lists, displaying items).
Together they create real logic — combining loops with conditionals lets programs handle complex tasks efficiently (e.g., iterate through data and apply conditions).

Conditional Statements 🔀

Very often when you write code, you want to perform different actions for different decisions. You can use conditional statements in your code to do this.

1️⃣ If statement

If you want to execute some code only if a specified condition is true.

// Syntax
if (condition) 
{ 
code to be executed if condition is true 
} 

// Example
if (time<10)  
{ 
document.write("<b>Good morning</b>"); 
}

2️⃣ If....else statement

If you want to execute some code if a condition is true and another code if the condition is not true,

// Syntax
if (condition) 
{ 
code to be executed if condition is true 
} 
else 
{ 
code to be executed if condition is not true 
} 

// Example
if (time < 10)  
{ 
document.write("Good morning!"); 
} 
else 
{ 
document.write("Good day!"); 
}

3️⃣ Switch statement

If you want to select one of many blocks of code to be executed.

// Syntax
switch(expression) 
{ 
case label-1: 
  execute code block 1 
  break;     
case label-2: 
  execute code block 2 
  break; 
default: 
  code to be executed if expression is 
  different from label-1 and label-2 
} 

// Example
switch (theDay) 
{ 
case 5: 
  document.write("Finally Friday"); 
  break; 
case 6: 
  document.write("Super Saturday"); 
  break; 
case 0: 
  document.write("Sleepy Sunday");
  break; 
default: 
document.write("I'm looking forward to this weekend!"); 
}

Looping Statements 🔁

Very often when you write code, you want the same block of code to run over and over again in a row. Instead of adding several almost equal lines in a script we can use loops to perform a task like this.

1️⃣ for loop

The for loop is used when you know in advance how many times the script should run.

// Syntax
for (initialisation ; condition ; increment/decrement )  
{ 
code to be executed 
}

// Example
for(var i = 1; i <= 10; i++)
{
  console.log(i);
}

2️⃣ while loop

The while loop is used when you want the loop to execute and continue executing while the specified condition is true.

// Syntax
Initialisation
while (condition) 
{ 
    code to be executed
    Update variable 
}

// Example
var i=0; 
while (i <= 10) 
{ 
  console.log(i);
  i=i+1; 
}

3️⃣ do....while loop

This loop will always be executed at least once, even if the condition is false, because the code is executed before the condition is tested.

// Syntax
Initialisation
do 
{ 
    code to be executed
    Update variable
} 
while (condition);

// Example
var i=0; 
do  
{ 
    console.log(i);
    i=i+1; 
} 
while (i <= 10);

finish

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