Different Kinds of For Loop in C Programming

Different Ways of Using For Loop in C Programming

In order to do certain actions multiple times , we use loop control statements.
For loop can be implemented in different verities of using for loop -

1. Single Statement inside For Loop
2. Multiple Statements inside For Loop
3. No Statement inside For Loop
4. Semicolon at the end of For Loop
5. Multiple Initialization Statement inside For
6. Missing Initialization in For Loop
7. Missing Increment/Decrement Statement
8. Infinite For Loop
9. Condition with no Conditional Operator.

Way 1 : Single Statement inside For Loop

for(i=0;i<5;i++)
  printf("Hello");

1. Above code snippet will print Hello word 5 times.
2. We have single statement inside for loop body.
3. No need to wrap printf inside opening and closing curly block.
4. Curly Block is Optional.

Way 2 : Multiple Statements inside For Loop

for(i=0;i<5;i++)
   {
   printf("Statement 1");
   printf("Statement 2");
   printf("Statement 3");
   if(condition)
       {
       --------
       --------
       }
   }

If we have block of code that is to be executed multiple times then we can use curly braces to wrap multiple statement in for loop.

Way 3 : No Statement inside For Loop

for(i=0;i<5;i++)
   {
   }

this is bodyless for loop. It is used to increment value of “i”.This verity of for loop is not used generally.

Way 4 : Semicolon at the end of For Loop

for(i=0;i<5;i++);

1. Generally beginners thought that , we will get compile error if we write semicolon at the end of for loop.
2. This is perfectly legal statement in C Programming.
3. This statement is similar to bodyless for loop. (Way 3)

Way 5 : Multiple Initialization Statement inside For

for(i=0,j=0;i<5;i++)
   {
   statement1;
   statement2;
   statement3;
   }

Way 6 : Missing Increment/Decrement Statement

for(i=0;i<5;)
   {
   statement1;
   statement2;
   statement3;
   i++;
   }

however we have to explicitly alter the value i in the loop body.

Way 7 : Missing Initialization in For Loop

i = 0;
for(;i<5;i++)
   {
   statement1;
   statement2;
   statement3;
   }

we have to set value of ‘i’ before entering in the loop otherwise it will take garbage value of ‘i’.

Way 8 : Infinite For Loop

i = 0;
for(;;)
   {
   statement1;
   statement2;
   statement3;
   if(breaking condition)
      break;
   i++;
   }

Infinite for loop must have breaking condition in order to break for loop. otherwise it will cause overflow of stack.

Summary of Different Ways of Implementing For Loop