Infinite Loops mistakes

• Mistake: Creating a loop that never terminates, usually due to an incorrect or missing loop condition.
• Solution: Always verify your loop conditions and ensure that there is a clear exit point. For example, if using a while loop, check that the condition will eventually become false.

🔁 What is an Infinite Loop?

An infinite loop is a loop that never stops executing because its termination condition is never met or is missing.

That means — once it starts, it keeps running forever (until the program is forcibly stopped).

⚠️ Common Mistakes That Cause Infinite Loops in Java

1️⃣ Wrong or Missing Update Statement

If you forget to update the loop variable, the condition never changes.

int i = 1;
while (i <= 5) {
    System.out.println("Hello");
    // i++;   // ❌ Missing increment causes infinite loop
}

✅ Correct version:

int i = 1;
while (i <= 5) {
    System.out.println("Hello");
    i++;   // ✅ Updates loop variable
}

2️⃣ Incorrect Condition

If you use the wrong logical operator or condition, the loop may never end.

int i = 1;
while (i != 5) {   // ❌ If i keeps skipping 5, it never ends
    System.out.println("i = " + i);
    i += 2; // 1, 3, 5, 7... it will skip 5 → Infinite loop
}

✅ Correct version:

int i = 1;
while (i <= 5) {
    System.out.println("i = " + i);
    i += 2;
}

3️⃣ Always True Condition

If the condition is always true, the loop never ends.

while (true) {
    System.out.println("I will run forever!");
}

👉 Such loops are intentional sometimes (e.g., servers),
but for beginners, this is often a mistake.

4️⃣ Floating-Point Comparison Errors

When using floating-point numbers (float or double) as loop variables, precision errors can cause infinite loops.

for (double d = 0.1; d != 1.0; d += 0.1) {
    System.out.println(d);
}

⚠️ d may never be exactly equal to 1.0 due to floating-point rounding.

✅ Better:

for (int i = 1; i < 10; i++) {
    double d = i / 10.0;
    System.out.println(d);
}

5️⃣ Using Wrong Operator in Condition

Mistaking = for == (assignment instead of comparison).

int a = 1;
while (a = 5) {  // ❌ Error: using = instead of ==
    System.out.println("Wrong!");
}

✅ Correct:

int a = 1;
while (a == 5) {
    System.out.println("Correct!");
}

6️⃣ Logic Errors in For Loops

If the loop variable moves away from the condition instead of toward it.

for (int i = 10; i >= 1; i++) {   // ❌ increasing i but checking for >=
    System.out.println(i);
    i++; // moves away from termination → infinite loop
}

✅ Correct:

for (int i = 10; i >= 1; i--) {
    System.out.println(i);
}

💡 How to Avoid Infinite Loops

✅ Always check:

1. Is the loop variable initialized properly?

2. Does it change inside the loop?

3. Will the condition eventually become false?

🧠 Example: Intentional Infinite Loop (Safe Exit)

Sometimes you may want an infinite loop that breaks with a condition:

while (true) {
    int num = (int)(Math.random() * 10);
    System.out.println("Number: " + num);
    if (num == 5)
        break; // ✅ Exit when condition is met
}