What is difference between for and for each loop.

What is difference between for and for each loop.Please explain with a example.

Prabhash
30 Apr 2026
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12 Answers

Birender
14 May 2020

For-each loop in Java Prerequisite:&nbsp;<a rel='nofollow' href="https://www.geeksforgeeks.org/decision-making-javaif-else-switch-break-continue-jump/">Decision making in Java</a> For-each is another array traversing technique like for loop, while loop, do-while loop introduced in Java5. * It starts with the keyword&nbsp;for&nbsp;like a normal for-loop. * Instead of declaring and initializing a loop counter variable, you declare a variable that is the same type as the base type of the array, followed by a colon, which is then followed by the array name. * In the loop body, you can use the loop variable you created rather than using an indexed array element. * It&rsquo;s commonly used to iterate over an array or a Collections class (eg, ArrayList) Syntax: for (type var : array) { statements using var; } is equivalent to: for (int i=0; i&lt;arr.length; i++) { type var = arr[i]; statements using var; } // Java program to illustrate&nbsp; // for-each loop class For_Each&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;public static void main(String[] arg) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;int[] marks = { 125, 132, 95, 116, 110 }; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;int highest_marks = maximum(marks); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println(&quot;The highest score is &quot; + highest_marks); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp;public static int maximum(int[] numbers) &nbsp;&nbsp;&nbsp;&nbsp;{&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;int maxSoFar = numbers[0]; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;// for each loop &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;for (int num : numbers)&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if (num &gt; maxSoFar) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;maxSoFar = num; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp;return maxSoFar; &nbsp;&nbsp;&nbsp;&nbsp;} } Output: The highest score is 132 Limitations of the for-each loop 1. For-each loops are&nbsp;not appropriate when you want to modify the array: for (int num : marks) { // only changes num, not the array element num = num*2; } 2. For-each loops&nbsp;do not keep track of index. So we can not obtain array index using For-Each loop for (int num : numbers) { if (num == target) { return ???; // do not know the index of num } } 3. For-each&nbsp;only iterates forward over the array in single steps // cannot be converted to a for-each loop for (int i=numbers.length-1; i&gt;0; i--) { System.out.println(numbers[i]); } 4.For-each&nbsp;cannot process two decision making statements&nbsp;at once // cannot be easily converted to a for-each loop for (int i=0; i&lt;numbers.length; i++) { if (numbers[i] == arr[i]) { ... } }

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For-each loop in Java
Prerequisite: Decision making in Java
For-each is another array traversing technique like for loop, while loop, do-while loop introduced in Java5.

* It starts with the keyword for like a normal for-loop.
* Instead of declaring and initializing a loop counter variable, you declare a variable that is the same type as the base type of the array, followed by a colon, which is then followed by the array name.
* In the loop body, you can use the loop variable you created rather than using an indexed array element.
* It’s commonly used to iterate over an array or a Collections class (eg, ArrayList)

Syntax:

for (type var : array) { statements using var; }

is equivalent to:

for (int i=0; i<arr.length; i++) { type var = arr[i]; statements using var; }
// Java program to illustrate
// for-each loop
class For_Each
{
 public static void main(String[] arg)
 {
 {
 int[] marks = { 125, 132, 95, 116, 110 };

 int highest_marks = maximum(marks);
 System.out.println("The highest score is " + highest_marks);
 }
 }
 public static int maximum(int[] numbers)
 {
 int maxSoFar = numbers[0];

 // for each loop
 for (int num : numbers)
 {
 if (num > maxSoFar)
 {
 maxSoFar = num;
 }
 }
 return maxSoFar;
 }
}

Output:

The highest score is 132
Limitations of the for-each loop

1. For-each loops are not appropriate when you want to modify the array:

for (int num : marks)
{
// only changes num, not the array element
num = num*2;
}

2. For-each loops do not keep track of index. So we can not obtain array index using For-Each loop

for (int num : numbers)
{
if (num == target)
{
return ???; // do not know the index of num
}
}

3. For-each only iterates forward over the array in single steps

// cannot be converted to a for-each loop
for (int i=numbers.length-1; i>0; i--)
{
System.out.println(numbers[i]);
}

4.For-each cannot process two decision making statements at once

// cannot be easily converted to a for-each loop
for (int i=0; i<numbers.length; i++)
{
if (numbers[i] == arr[i])
{ ...
}
}

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