Use of goto Statement

Using goto Statement

goto statement is used to jump on a particular location in a program defined by label. Label is a name given to a location. 
Label is defined by a <locationName> followed by a colon.
goto is use with goto <labelName>;

syntax of label & goto

statment 1;
label: //syntax of label
statment 2;
statment 3;
if(statement) //if condition true
{
goto label;
//jump to label i.e. after statement 1 and program will execute again statement 2 and 3
}


Let Check out Example for better understanding

Ex1: Print first 10 Natural Number
#include<iostream.h>
int main()
{
    int i=1; 
    print:
    cout << i <<endl; 
    if(i<10) 
    {
        i++; 
        goto print; //jump to print label as define above after initialization of i
    }
/*
In Above Program we are printing first 10 natural number using goto statment
in this example goto is used as loop to print 1 to 10
first we initialize the variable i to 1
then we define a checkpoint or label for using with goto
then we print value of variable i
we check if variable i is less than 10 if true then increment of variable i and jump to checkpoint or label we define earlier to print again this process continue till condition is false similar in a loop
*/
 return 0;
}

OUTPUT

Ex2: Divide Two Numbers [check this program using loop]
#include<iostream.h>
int main()
{
//Divide Two Numbers
    char ch;
    float a,b;
    tryAgain:
    cout << "Enter First Number : ";
    cin >> a; //Input First Number
    cout << "Enter Second Number : ";
    cin >> b; //Input Second Number
    if(b == 0) // Check for divisor for zero
    {
        cout << "Error: Number Cannot Divide by Zero"<<endl; //return error message
        goto tryAgain;
    }
    cout << "Answer = " << a/b<<endl;

    cout << "Try Again(y/n): ";
    if(cin >> ch && ch != 'n') 
        goto tryAgain;

  /*
In this example we are dividing two number and check for divisor not equal to zero
first we define label before taking input from user 
then we take input two numbers 
if (divisor(here b) = 0) then print error message and goto label; that jump back to a point where we have to take input again
now if divisor is not zero then we print answer and ask user for more
here you can see expression in if condition 
if(cin>> ch && ch != 'n')
above if statement has two conditions for check as there is AND(&&) between them means both must be true
check each conditions cin >> ch this will return true when it take input successfully 
and then it compare ch != 'n'
means here we are do two operation that first we take input and check for equality in one statement
second condition will run only when we get input from first statement
so if its true then it goto label; 
else <end of program>
*/
    return 0;
}

Output

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Use of Continue Statement

Using Continue Statement

Continue statement is used to skip the current iteration and force to execute next iteration by skipping any code after continue statement inside a loop.
In simple term whenever you encounter continue statement in a loop it will skip the current pass execute next pass and also it skip the other statement below the continue statement inside a loop.

Let check the following examples for better understanding:

Ex1: Print Odd Number
#include<iostream.h>
int main()
{
//Print odd number
for(int i=1; i<=10;i++)
 {
    if(i%2==0)
    continue;
/*
 Above two lines first line check if i is even or not, If its even then i%2 return zero
means condition is true for even number of i then continue statement will execute.
As you can see in output we are printing only odd numbers so whenever continue statement runs it will skip all next line inside a loop and go to next iteration that increment of i
*/
    cout << i<<endl;
 }
return 0;
}

OUTPUT

Ex2: Divide Two Numbers
#include<iostream.h>
int main()
{
//Divide Two Numbers
char ch;
float a,b;
do //Using Do While Loop
 {
  cout << "Enter First Number : "; 
  cin >> a; //Input First Number

  cout << "Enter Second Number : ";
  cin >> b; //Input Second Number

  if(b == 0) // Check for divisor for zero

   {

    cout << "Error: Number Cannot Divide by Zero"<<endl; //return error message

    continue; 

/*

In this whenever we encounter with divisor = 0 then error message is display

and continue statement will execute. Whenever Continue statement runs it will skip all the code after that inside a loop and start from next iteration. As in this example we are using Do while loop which check condition at the end but we already skip the statements after continue so we will don't check the condition and we will start loop from begin. As you can seen in Output

*/

   }

  cout << "Answer = " << a/b<<endl;

  

  cout << "Try Again(y/n): ";

  cin >> ch; 

 }while(ch != 'n');

 return 0;

}

Output

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