Algorithm Repetition

Today in algorithm class i learn repetition.

so what is repetition?

Repetition is

•   One or more instruction repeated for certain  amount of time
• ·Number of repetition can be predefined (hard-coded in program) or defined later at   run time
• there are a couple of Repetition operation:
  • For
  • While
  • Do-while

1.For            Example of For:

•   Program to print out numbers from 1 to 10 :

      

#include<stdio.h>

int main()

{

    int x;

    for( x = 1 ;  x <= 10 ;  x++ ) printf( "%d\n", x );

    return(0);

}

• Program to print out numbers from 10 to 1  :

#include<stdio.h>

int main()

{

    int x;

    for( x = 10 ;  x >= 1 ;  x-- ) printf( "%d\n", x);

    return(0);

}

  

• Infinite Loop :
  Loop with no stop condition can use “for-loop” by removing all parameters (exp1, exp2, exp3). To end the loop use break.  

•  Nested Loop :

           Loop in a loop. The repetition Operation will start from the inner side loop.

2.While 

     while (exp) statements;

• exp is Boolean expression. It will result in true (not zero) or false (equal to zero).
• Statement will be executed while the exp is not equal to zero.
• exp evaluation is done before the statements executed.

      Example :

while(product <= 1000) product = 2*product;

 

3.Do-while

• Keep executing while statement is true
• Statement evaluation done after executing the statement(s)

  Example:

•  do{printf("%d\n",counter);}

      while(++counter <= 10);

  



Reference from binusmaya Algorithm and Programming class
resource session 9 (program control : repetition)