3f6a61fbca
* Add the text article Infinite Loop to my article The article "##Infinite Loop by opposite iteration##" gives an example to new java programmer as to how a program can go into infinite loop if we increment the value of i instead of decrementing it and vice-versa. It is a basic but an important example for new coders. * Update index.md * Add Infinite Loop by update This article will give new programmers the example of infinite loop when we increment the value instead of decrementing and vice-versa. * Fixed several formatting issues
88 lines
2.3 KiB
Markdown
88 lines
2.3 KiB
Markdown
---
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title: Infinite Loops
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---
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# Infinite Loops
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An infinte loop is a loop statement (`for`, `while`, `do-while`) which does not end on its own.
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The test condition of a looping statement decides whether the loop body will execute or not. So a test condition which is always true will keep on executing the body of the loop, forever. That's the case in an infinte loop.
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Examples:
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```java
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// Infinite For Loop
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for ( ; ; )
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{
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// some code here
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}
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// Infinite While Loop
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while (true)
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{
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// some code here
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}
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// Infinite Do While Loop
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do
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{
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// some code here
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} while (true);
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```
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Normally, if your loop is running infinitely, it is an error that should not occur as an infinite loop does not stop and prevents the rest of the program from running.
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```java
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for(int i=0;i<100;i++){
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if(i==49){
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i=0;
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}
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}
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```
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The loop above runs infinitely because every time i approaches 49, it is set to be 0.This is to say that i never reaches 100 to terminate the loop, so the loop is an infinite loop.
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But a program stuck in such a loop will keep using computer resources indefinitely. This is undesirable, and is a type of 'run-time error'.
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#### Infinite Loop by opposite iteration
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Another example of an Infinite Loop can be seen below:
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```java
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for(int i=0;i<=10;i--)
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System.out.println(i);
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```
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In the above example, the initial value of `i` is 0. Since value of `i` is less than equal to 10, we decrement the value of `i` by 1, so `i` will now be -1. Hence, the loop will be infinite.
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Similarly, an example of an infinite while loop example can be seen below:
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```java
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int i=1;
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while(i>=1)
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{
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System.out.println(i);
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i+=1;
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}
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```
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Here, `i` will always be greater than 1, so the program will be in an infinite loop.
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To prevent the error, programmers use a `break` statement to break out of the loop. The `break` executes only under a particular condition. Use of a selection statement like `if-else` ensures the same.
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```java
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while (true)
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{
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// do something
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if(conditionToEndLoop == true)
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break;
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// do more
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}
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```
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The main advantage of using an infinite loop over a regular loop is readability.
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Sometimes, the body of a loop is easier to understand if the loop ends in the middle, and not at the end/beginning. In such a situation, an infinite loop will be a better choice.
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