C++ Break

In this C++ tutorial, you will learn about break statement, and how to use break statement to break looping statements, or switch statement, with example programs.

C++ Break Statement

Break statement ends the execution of surrounding loop. In other words it breaks the loop even before the loop condition becomes false.

You can apply break statement to while loop, do-while loop, for loop and a switch statement.

Syntax of Break

Following is the syntax of break statement.

break;

Please note that you can use break statement only within a loop or switch statement.

Break While loop

Break statement can be used to break a C++ While Loop abruptly.

In the following example, while loop tries to print numbers from 0 to 9. But during fourth iteration when i becomes 4, break statement ends the execution of this while loop.

C++ Program

#include <iostream>
using namespace std;

int main() {
   int i=0;
   while (i < 10) {
      if (i==4) {
         break;
      }
      cout << i << "  ";
      i++;
   }
}

Output

0  1  2  3

Break Do-while loop

Break statement can be used to break a C++ Do-While Loop abruptly.

In the following example, do-while loop tries to print numbers from 0 to 9. But during fifth iteration when i becomes 5, break statement ends the execution of this while loop.

C++ Program

#include <iostream>
using namespace std;

int main() {
   int i=0;
   do {
      if (i==5) {
         break;
      }
      cout << i << "  ";
      i++;
   } while (i < 10);
}

Output

0  1  2  3  4

Break For loop

You can break a C++ For Loop abruptly using a break statement.

In the following example, we have written a for loop to print numbers from 0 to 9. Also, we have conditionally employed a break statement to execute when the number reaches 7. When break statement executes, the program control comes out of the surrounding for loop.

C++ Program

#include <iostream>
using namespace std;

int main() {
   for (int i=0; i < 10; i++) {
      if (i==7) {
         break;
      }
      cout << i << "  ";
   }
}

Output

0  1  2  3  4  5  6

Break in Switch-case statement

In C++ Switch Statement, break statement is usually written at the end of each case block.

Following is an example C++ program with Switch statement containing break statements.

C++ Program

#include <iostream>
using namespace std;

int main() {
   int day = 25;
   switch (day%7) {
      case 1: {
         cout << "Monday" << endl;
         break;
      }
      case 2: {
         cout << "Tuesday" << endl;
         break;
      }
      case 3: {
         cout << "Wednesday" << endl;
         break;
      }
      case 4: {
         cout << "Thursday" << endl;
         break;
      }
      case 5: {
         cout << "Friday" << endl;
         break;
      }
      default: {
         cout << "Off day" << endl;
      }
   }
}

Output

Thursday

Break in Nested Loop

Break statement affects only its surrounding loop. So, if you are using a break statement in a nested loop, please note that it breaks only its surrounding loop.

In the following example, we shall write a break statement inside nested while loop. The program prints a pattern.

C++ Program

#include <iostream>
using namespace std;

int main() {
   int i = 1;
   while (i <= 5) {
      int j = 1;
      while (j <= 5) {
         if(j>i) {
            break;
         }
         cout << " *";
         j++;
      }
      cout << "\n";
      i++;
   }
}

Output

*
 * *
 * * *
 * * * *
 * * * * *

Break in If-else statement

We know that break statement could be written only inside a looping statement or switch-case statement.

In the following example, we shall write a break statement inside C++ If Else statement, with no loop or switch wrapping this if-else statement.

C++ Program

#include <iostream>
using namespace std;

int main() {
   int n = 20;
   if (n%2 == 0) {
      if(n%10 == 0) {
         break;
      }
      cout << "something even" << endl;
   } else {
      cout << "odd" << endl;
   }
}

Output

d:\workspace\cpp\main.cpp:8:10: error: break statement not within loop or switch
    8 |          break;
      |          ^~~~~
The terminal process terminated with exit code: 1

We got a compilation error stating that break statement is not within loop or switch.

Conclusion

In this C++ Tutorial, we learned about break statement, what it does to surrounding loop statements, with example C++ programs.