Loop Statement in C# , Control Structure in C#, For Loop, While Loop and Do While Loop Concept in C#

Author - Shiva Gautam
8/22/2020
17
Loop Statement in C#, Control Structure in C#, For Loop, While Loop and Do While Loop Concept in C#:-

Loop is used to print or enumerate large statements of data using a single repeatable block, Loop is also called an iterative statement because it will repeat the data according to condition.


Type of Loop:-

1)Entry Control Loop:-

First check condition then execute loop statements hence it is called entry control.

1.1)  While Loop:-

          Syntax of While Loop:-

                init;
               while(condition)
               {
                          Statement;
                          Increment;

               }



Now I am discussing one simple program of while loop, suppose I want to display a range of elements from1 to 100?

Solution:-

int i=1;
while(i<=100)
{

      Console.WriteLine(i);
      i++;

}

suppose I want to display a range of elements from100 to 1?

Solution:-

int i=100;
while(i>=1)
{

      Console.WriteLine(i);
      i--;

}


Write a program to calculate a table of any number using a complete expression?

class CalculateTable
    {
        static void Main()
        {
            int num,i;
            Console.WriteLine("Enter number to print table");
            num = int.Parse(Console.ReadLine());
            i = 1;
            while (i <= 10)
            {
                Console.WriteLine("{0}*{1}={2}",num,i,num * i);
                i++;
            }
            Console.ReadKey();
        
        }
    }

Infinite While Loop in C#:-

Infinite loop means, loop without any finite condition for example if we pass true under while loop, then it will automatically be converted into the infinite while loop.

When we want to create an infinite loop in C# then we prefer while loop Otherwise we will use for Loop




Syntax of Infinite While Loop:-

while(true)
{
        Statements;

}


Example of Infinite While Loop:-


class WhileExample
    {
        public static void Main()
        {
            int i = 1;
            while (true)
            {
                Console.WriteLine(i);
                i++;
                if (i == 10)
                    break;
            }
            Console.ReadKey();
        }
    }



Another Example of Infinite While Loop:-

 class WhileExample
    {
        static void Main()
        {
            bool flag = true;
            int x = 0;
            while (flag)
            {
                Console.WriteLine("hello"+x);
                x++;
                if (x > 10)
                {
                    flag = false;
                }

            }

            Console.ReadKey();

        }
    }

Create Lift based Program using While Loop:-

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Csharpfundamental
{
    internal class WhileLoopExample
    {
        static void Main()
        {
            int i = 1;
            int f = 1;
            bool p = true;
            while(i<=10 && p)
            {
                if (i <= 5)
                {
                    Console.WriteLine("floor "+f);
                    Thread.Sleep(2000);
                    f++;
                }
                else
                {
                    p = false;
                    f--;
                    Console.WriteLine("floor " +f);
                    Thread.Sleep(2000);

                }
                i++;
            }
        }
    }
}


While Loop Assignment:-

1)  WAP to check prime number?

2)  WAP to calculate factorial with expression?

    5!

    5*4*3*2*1=120
3) WAP to print Fibonacci series with expression

   0+1=1
   1+0=1
   1+1=2
   1+2=3
   3+2=5

4)  WAP to create lift for 10th floor building

5)  WAP to calculate sum of two digit positive number?


1.2)   For Loop:- 

This Loop will contain all statements (initialization, condition, and iteration) using a single statement. that's why for loop provides a simple syntax structure as compared to the while loop. we always prefer for  loop to solve range-based problems.

Syntax of for loop:-
      
     1      2               4

for(init;condition;iteration)
    {
           3
          Statement;
    }


WAP to check the prime number?

using System;


namespace ConsoleApplication2
{
    class CheckPrime
    {
        static void Main()
        {
            int num;
            Console.WriteLine("Enter number");
            num = int.Parse(Console.ReadLine());
            int c = 0;
            for (int i = 1; i <= num; i++)
            {
                if (num % i == 0)
                    c++;
            }
            if (c == 2)
                Console.WriteLine("Prime");
            else
                Console.WriteLine("Not Prime");
            Console.ReadKey();
        }
    }
}



WAP to check prime number without using the third variable?


class CheckPrime
    {
        static void Main()
        {
            int num,i;
            Console.WriteLine("Enter number");
            num = int.Parse(Console.ReadLine());
         
            for (i = 2; i < num; i++)
            {
                if (num % i == 0)
                {
                    Console.WriteLine("Not Prime");
                    break;
                }
            }
            if (num==i)
                Console.WriteLine("Prime");
         
             
            Console.ReadKey();
        }
    }


WAP to check prime number with complete program optimization?

class CheckPrime
    {
        static void Main()
        {
            int num,i;
            Console.WriteLine("Enter number");
            num = int.Parse(Console.ReadLine());
         
            for (i = 2; i < num/2; i++)
            {
                if (num % i == 0)
                {
                    Console.WriteLine("Not Prime");
                     break;
                }
            }
            if (num/2==i)
                Console.WriteLine("Prime");
         
             
            Console.ReadKey();
        }
    }




2) Exit Control Loop:-

First, execute the loop statement then check the condition, this loop will not use mostly on application programming.

2.1)  do--while:-   

First, execute the statement then check the condition.

Syntax of Do--While Loop:-

init;
do
{
      Statement;
      Increment;

}while(condition);


WAP to print 1 to 10 and 10 to 1 using do-while Loop?


class DoWhileExample
    {
        public static void Main()
        {
            int i = 1;
            do
            {
                if (i <= 10)
                    Console.WriteLine(i);
                else
                    Console.WriteLine(21-i);
                i++;
            } while (i <= 20);
            Console.ReadKey();
        }
    }


Q) Program to implement Fibonacci series?

using System;
// 0 1 1 2 3 5 8 13
class DowhileExample
{
    public static void Main()
     {
        int a=-1,b=1,c=0,i=1;
        do
        {
          c = a+b;
          Console.WriteLine(c);
          a=b;
          b=c;
          i=i+1;

        }while(i<=10);


     }

}
ASSIGNMENT of LOOP:-


 1)  WAP to check prime number without using a third variable?

3)  WAP to find the first, second, and third max number in pin code?

2)  WAP to display the table of each Fibonacci series digit?

0 1 1 2 3 5 8 13
WAP to check prime number with complete expression

5    5%2,5%3,5%4
WAP to print factorial with expression

5*4*3*2*1=120


4) WAP  to check that a particular digit exists in a mobile number or not and display the number of times?




                          



Tags
Shiva Gautam

Shiva Gautam

Hi, I'm Shiva Gautam. With over 15 years of diverse experience in various IT domains, I am now an entrepreneur focusing on both training and software development. My expertise spans across multiple technologies, and I've authored numerous articles on subjects including Java, Python, REACT, NODE, ANGULAR, Cloud, software testing, Django framework, C#, Flutter, Salesforce, Ruby on Rails, .NET, AWS, DEVOPS, AI/ML and more. For additional information, please visit shivaconceptsolution.com and kangaroosoftware.net.

You may like these posts

Show more

Post a Comment

17Comments

POST Answer of Questions and ASK to Doubt

  1. UnknownDecember 29, 2019 at 5:48 PM

    WAP to print factorial with expression


    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;

    namespace factorial
    {
    class Program
    {
    static void Main(string[] args)
    {
    int fact=1, i,num;
    Console.WriteLine("Enter a number to find factorial ");
    num = int.Parse(Console.ReadLine());

    for(i=num;i>=1;i--)
    {
    fact = fact * i;
    Console.Write("*");
    Console.Write(i*1 );


    }

    Console.WriteLine(" = " + fact);

    Console.ReadKey();
    }
    }
    }

    ReplyDelete
  2. UnknownDecember 30, 2019 at 7:49 AM

    WAP to display table of each Fibonacci series digit?


    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;

    namespace fabonacci
    {
    class Program
    {
    static void Main(string[] args)
    {
    int a = -1 , b = 1 ,c;


    for (int i = 1; i <= 6; i++)
    {
    c = a + b;


    if (c > 0)
    {
    Console.WriteLine("Table of " + c);
    for (int j = 1; j <= 10; j++)
    {

    Console.WriteLine(c * j);
    }


    }
    a = b;
    b = c;


    }

    Console.ReadKey();
    }
    }
    }

    ReplyDelete
  3. UnknownMarch 6, 2021 at 10:20 PM

    #Shiva_Patel

    Ans:- Find Prime number with two variables

    int num,i;
    Console.WriteLine("Enter number");
    num = int.Parse(Console.ReadLine());
    for(i=2; i<num; i++)
    {
    if (num%i == 0)
    {
    Console.WriteLine("Not Prime");
    break;
    }
    }
    if(num==i)
    Console.WriteLine("{0} is Prime",num);

    ReplyDelete
  4. UnknownJuly 5, 2021 at 10:33 AM

    program to check if a particular digit present in a phone number


    using System;
    class digit
    {
    public static void Main()
    {
    double i,a,b,c;
    Console.WriteLine("enter phone number");
    i=double.Parse(Console.ReadLine());
    Console.WriteLine("enter digit which you wanna check");
    c=int.Parse(Console.ReadLine());
    while(i!=0)
    {
    a=i%10;
    b=a;
    i/=10;
    if(b==c)
    {
    Console.WriteLine("number is present");
    break;
    }

    }
    if (i==0)
    {
    Console.WriteLine("number is not present");
    }
    }
    }

    ReplyDelete
  5. harsh murarMay 22, 2024 at 11:51 AM

    namespace First_project
    {
    internal class WhilePrimeNo
    {
    public void whileprimeno()
    {
    Console.WriteLine("Enter any NO.");
    int num =int.Parse(Console.ReadLine());
    int i=2;
    while (i < num)
    {
    if (num%i == 0)
    {
    Console.WriteLine("not prime");
    break;
    }
    i++;
    if (num == i)
    {
    Console.WriteLine("prime");
    }
    }



    }

    }
    }

    ReplyDelete
  6. harsh murarMay 22, 2024 at 12:32 PM

    factorial while loop
    namespace First_project
    {
    internal class WhileFactorial
    {
    public void whilefactorial()
    {
    Console.WriteLine("Enter any No.");
    int num=int.Parse(Console.ReadLine());
    int i = 1;
    int f = 1;
    while (i <=num)
    {
    f = f * i;
    i++;
    Console.WriteLine(i-1+"*");
    }
    Console.WriteLine(f);
    }
    }
    }

    ReplyDelete
  7. harsh murarMay 22, 2024 at 2:41 PM

    fibonacci
    namespace First_project
    {
    internal class WhileFabonacci
    {
    public void whilefabonacci()
    {
    Console.WriteLine("Enter any no.");
    int num=int.Parse(Console.ReadLine());
    int i = 1, num1 = 0, num2 = 1, sum=1;
    while (i <= num)
    {
    Console.WriteLine(sum);
    sum = num1 + num2;
    num1 = num2;
    num2 = sum;
    i++;
    }
    }
    }
    }

    ReplyDelete
  8. harsh murarMay 22, 2024 at 3:10 PM

    Lift
    namespace First_project
    {
    internal class LiftFor10Floor
    {
    public void liftfor10floor()
    {
    Console.WriteLine("Please enter the current Floor You are");
    int cfloor=int.Parse(Console.ReadLine());
    Console.WriteLine("Please enter the Floor You want to go");
    int floor=int.Parse(Console.ReadLine());
    int i = cfloor;
    if (floor > cfloor && floor <= 10)
    {
    while (i <= floor)
    {
    Console.WriteLine(i++);
    Thread.Sleep(1000);
    }
    }
    else if (floor < cfloor && floor >= 0)
    {
    while (i >= floor)
    {
    Console.WriteLine(i--);
    Thread.Sleep(1000);
    }
    }
    else Console.WriteLine("Wrong Input");

    }
    }
    }

    ReplyDelete
  9. harsh murarMay 23, 2024 at 12:37 PM

    Prime no by for loop
    {

    Console.WriteLine("Enter any No.");
    int num= int.Parse(Console.ReadLine());
    for (int i=2; i<num; i++)
    {
    if (num % i == 0)
    {
    Console.WriteLine("Not Prime");
    break;
    }
    Console.WriteLine("prime no.");
    break;
    }

    }

    ReplyDelete
  10. harsh murarMay 23, 2024 at 12:58 PM

    Fibonacci by For loop
    public void forfibonacci()
    {
    Console.WriteLine("Enter any No.");
    int num = int.Parse(Console.ReadLine());
    int num1 = 0, num2 = 1, sum = 1;
    for (int i = 0; i < num; i++)
    {
    sum = num1 + num2;
    Console.WriteLine("{0} + {1} = {2}", num1, num2, sum);
    num1 = num2;
    num2 = sum;
    }
    }

    ReplyDelete
  11. harsh murarMay 23, 2024 at 1:39 PM

    Factorial by For loop
    public void forfactorial()
    {
    Console.WriteLine("Enter any No.");
    int num = int.Parse(Console.ReadLine());
    int f = 1;
    string s = "";

    for (int i = num; i > 1; i--)
    {
    s = s + i + "x";
    f = f * i;
    }
    Console.WriteLine(s+"1="+ f);
    }

    ReplyDelete
  12. PriyankaMay 24, 2024 at 2:15 PM

    lift for 10th floor building
    namespace CsharpPrograming
    {
    internal class lift
    {
    static void Main()
    {
    int i = 1;

    while (i <= 10)
    {
    Console.WriteLine("floor"+i);
    Thread.Sleep(1000);
    i++;
    }
    }
    }
    }

    ReplyDelete
  13. PriyankaMay 24, 2024 at 2:17 PM

    Fibonacci series with expression
    internal class fibona
    {
    static void Main()

    {
    Console.WriteLine("Enter the number");
    int num = Convert.ToInt32(Console.ReadLine());

    int n1 = 0;
    int n2 = 1;

    Console.WriteLine(n1+"+"+n1+"="+n1);
    int i = 2;
    while (i< num)
    {
    int n3 = n1 + n2;
    Console.WriteLine(n1 + "+" + n2 + "=" +n3);
    n1 = n2;
    n2 = n3;
    ++i;

    }
    }
    }
    }

    ReplyDelete
  14. PriyankaMay 24, 2024 at 2:19 PM

    factorial with expression
    internal class fact
    {
    static void Main()
    {
    Console.WriteLine("Enter a number to find factorial ");
    int num = Convert.ToInt32(Console.ReadLine());

    int i = num ;
    int f = 1;


    while (i >= 1)
    {
    f = f * i;

    Console.Write(i*1);
    Console.Write("*");
    i--;
    }
    Console.WriteLine(" = " + f);
    }
    }
    }

    ReplyDelete
  15. PriyankaMay 24, 2024 at 9:54 PM

    Pattern 1
    internal class Class4
    {
    static void Main()
    {
    for (int i = 5; i >=1; i--)
    {
    for (int j =5; j>i; j--)
    {
    Console.Write(" ");
    }
    for (int k=1; k<=i; k++)
    {
    Console.Write( k);
    }
    Console.WriteLine( );
    }
    }
    }
    }

    ReplyDelete
  16. harsh murarJune 10, 2024 at 3:18 PM

    Inverted Reverse Right Triangle number
    namespace First_project
    {
    internal class PatternOne
    {
    public void patternone()
    {
    int m = 5;
    for (int i = 1; i <=5; i++)
    {
    for (int j = 1; j<i; j++)
    {
    Console.Write(' ');
    }
    for (int k = 1; k <=m; k++)
    {
    Console.Write(k);
    }
    m--;
    Console.WriteLine();
    }

    }
    }
    }

    ReplyDelete
  17. harsh murarJune 10, 2024 at 3:54 PM

    Alternate Alphabet and number Pattern
    namespace First_project
    {
    internal class PatternTwo
    {
    public void patterntwo()
    {

    for (int i = 5; i >=1; i--)
    {
    char al = 'A';
    for (int j =1 ; j <=i; j++)
    {
    if (i % 2 == 0)
    {
    Console.Write(j);
    }
    else
    {
    Console.Write(al);
    al++;
    }
    }
    Console.WriteLine();
    }
    }
    }
    }

    ReplyDelete
Post a Comment
Share to other apps
Copy Post Link