goto Statement

C goto statement

The goto statement is known as jump statement in C. As the name suggests, goto is used to transfer the program control to a predefined label. The goto statment can be used to repeat some part of the code for a particular condition. It can also be used to break the multiple loops which can't be done by using a single break statement. However, using goto is avoided these days since it makes the program less readable and complecated.

Syntax:

1. label:   
2. //some part of the code;   
3. goto label;  

goto example

Let's see a simple example to use goto statement in C language.

1. #include <stdio.h>  
2. int main()   
3. {  
4.   int num,i=1;   
5.   printf("Enter the number whose table you want to print?");   
6.   scanf("%d",&num);  
7.   table:   
8.   printf("%d x %d = %d\n",num,i,num*i);  
9.   i++;  
10.   if(i<=10)  
11.   goto table;    
12. }  

Output:

Enter the number whose table you want to print?10
10 x 1 = 10
10 x 2 = 20
10 x 3 = 30
10 x 4 = 40
10 x 5 = 50
10 x 6 = 60
10 x 7 = 70
10 x 8 = 80
10 x 9 = 90
10 x 10 = 100

When should we use goto?

The only condition in which using goto is preferable is when we need to break the multiple loops using a single statement at the same time. Consider the following example.

1. #include <stdio.h>  
2. int main()   
3. {  
4.   int i, j, k;    
5.   for(i=0;i<10;i++)  
6.   {  
7.     for(j=0;j<5;j++)  
8.     {  
9.       for(k=0;k<3;k++)  
10.       {  
11.         printf("%d %d %d\n",i,j,k);  
12.         if(j == 3)  
13.         {  
14.           goto out;   
15.         }  
16.       }  
17.     }  
18.   }  
19.   out:   
20.   printf("came out of the loop");   
21. }  

0 0 0
0 0 1
0 0 2
0 1 0
0 1 1
0 1 2
0 2 0
0 2 1
0 2 2
0 3 0
came out of the loop