Understanding the break Statement in C: Usage and Examples

break statement

C supports three jump statements: break, continue, and return. These statements transfer control to another part of your program. Each is discusssed here. Two keywords, break and continue, can be used in loop statements to provide addi- tional controls. Using break and continue can simplify programming in some cases.

The break statement terminates the loop (for, while and do...while loop) immediately when it is encountered. The break statement is used with decision making statement such as if...else.

Syntax of break statement

break;

The simple code above is the syntax for break statement.

Flowchart of break statement

How break statement works?

Example of break statement

By using break, you can force immediate termination of a loop, bypassing the conditional expression and any remaining code in the body of the loop. When a break statement is encountered inside a loop, the loop is terminated and program control resumes at the next statement following the loop. Here is a simple example:

 
#include<stdio.h>
void main()
{ 
     int i;
      for(i=1;i<=10;i++){
        if(i==7){
            break;
        }
      printf("%d \n",i);
      }
}

Output

1
2
3
4
5
6
Press any key to continue . . .

As you can see, although the for loop is designed to run from 0 to 10, the break statement causes it to terminate early, when i equals 7

Example of break statement in while loop

// Using break to exit a while loop.
 
#include<stdio.h>
void main()
{ 
    int i = 0;
	while(i < 100) {
		if(i == 10) break; // terminate loop if i is 10
		printf("i:%d \n",i);
		i++;
		}
	printf("Loop complete. \n");
}
 

Output

i: 0
i: 1
i: 2
i: 3
i: 4
i: 5
i: 6
i: 7
i: 8
i: 9
Loop complete.
Press any key to continue . . .

C Break Statement with Inner Loop

When used inside a set of nested loops, the break statement will only break out of the innermost loop.

// Using break with nested loops.
 
#include<stdio.h>
void main()
{ 
   int i,j;
	for(i=0; i<2; i++) {
		printf("Pass %d",i);

		for(j=0; j<100; j++) {
			if(j == 10) break; // terminate loop if j is 10
			printf(" %d",j);
			}

		printf(" \n");
		}
	printf("Loops complete.\n");
	}
 

Output

Pass 0 0 1 2 3 4 5 6 7 8 9
Pass 1 0 1 2 3 4 5 6 7 8 9
Loops complete.
Press any key to continue . . .

Another Example of break Statement with Inner Loop

// Using break with nested loops.
 
#include<stdio.h>
void main()
{ 
     int i, j ;
      for(i=1;i<=2;i++){

                for(j=1;j<=3;j++){
                   if(i==2&&j==2){
                       break;
                     }
                 printf(" %d",i);
                 printf(" %d \n",j);
              }
        }
 }
 

Output

 
1 1
1 2
1 3
2 1
Press any key to continue . . .

the break statement in the inner loop only causes termination of that loop. The outer loop is unaffected.

1. More than one break statement may appear in a loop
2. The break that terminates a switch statement affects only that switch statement and not any enclosing loops.

Another Example

The Below program calculates the sum of maximum of 10 numbers. It's because, when the user enters negative number, the break statement is executed and loop is terminated.

// Program to calculate the sum of maximum of 10 numbers
// Calculates sum until user enters positive number

# include<stdio.h>
int main()
{
    int i;
    double number, sum = 0.0;

    for(i=1; i <= 10; ++i)
    {
        printf("Enter a n%d: ",i);
        scanf("%lf",&number);

        // If user enters negative number, loop is terminated
        if(number < 0.0)
        {
            break;
        }

        sum += number; // sum = sum + number;
    }

    printf("Sum = %.2lf",sum);
    
    return 0;
}

Output

Enter a n1: 2.4
Enter a n2: 4.5
Enter a n3: 3.4
Enter a n4: -3
Sum = 10.30
Press any key to continue . . .