Difference between for and while loop in C, C++, Java

for loop:

for loop provides a concise way of writing the loop structure. Unlike a while loop, a for statement consumes the initialization, condition and increment/decrement in one line thereby providing a shorter, easy to debug structure of looping.

Syntax:

for (initialization condition; testing condition; 
                              increment/decrement)
{
    statement(s)
}

Flowchart:

Example:

C

filter_none

edit
close

play_arrow

link
brightness_4
code

#include <stdio.h>
  
int main()
{
  
    int i = 0;
  
    for (i = 5; i < 10; i++) {
        printf("GFG\n");
    }
  
    return 0;
}

chevron_right


C++

filter_none

edit
close

play_arrow

link
brightness_4
code

#include <iostream>
using namespace std;
  
int main()
{
  
    int i = 0;
  
    for (i = 5; i < 10; i++) {
        cout << "GFG\n";
    }
  
    return 0;
}

chevron_right


Java

filter_none

edit
close

play_arrow

link
brightness_4
code

import java.io.*;
  
class GFG {
    public static void main(String[] args)
    {
  
        int i = 0;
  
        for (i = 5; i < 10; i++) {
            System.out.println("GfG");
        }
    }
}

chevron_right


Output:

GFG
GFG
GFG
GFG
GFG

while loop:

A while loop is a control flow statement that allows code to be executed repeatedly based on a given Boolean condition. The while loop can be thought of as a repeating if statement.
Syntax :

while (boolean condition)
{
   loop statements...
}

Flowchart:
while loop

Example:

C

filter_none

edit
close

play_arrow

link
brightness_4
code

#include <stdio.h>
  
int main()
{
  
    int i = 5;
  
    while (i < 10) {
        printf("GFG\n");
        i++;
    }
  
    return 0;
}

chevron_right


C++

filter_none

edit
close

play_arrow

link
brightness_4
code

#include <iostream>
using namespace std;
  
int main()
{
  
    int i = 5;
  
    while (i < 10) {
        i++;
        cout << "GFG\n";
    }
  
    return 0;
}

chevron_right


Java

filter_none

edit
close

play_arrow

link
brightness_4
code

import java.io.*;
  
class GFG {
    public static void main(String[] args)
    {
  
        int i = 5;
  
        while (i < 10) {
            i++;
            System.out.println("GfG");
        }
    }
}

chevron_right


Output:

GFG
GFG
GFG
GFG
GFG

Here are few differences:

For loop While loop
Initialization may be either in loop statement or outside the loop. Initialization is always outside the loop.
Once the statement(s) is executed then after increment is done. Increment can be done before or after the execution of the statement(s).
It is normally used when the number of iterations is known. It is normally used when the number of iterations is unknown.
Condition is a relational expression. Condition may be expression or non-zero value.
It is used when initialization and increment is simple. It is used for complex initialization.
For is entry controlled loop. While is also entry controlled loop.
for ( init ; condition ; iteration )
{ statement(s); }
while ( condition )
{ statement(s); }


My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.