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break Statement (C++)

The break statement ends execution of the nearest enclosing loop or conditional statement in which it appears. Control passes to the statement that follows the end of the statement, if any.

break;

Remarks

The break statement is used with the conditional switch statement and with the do, for, and while loop statements.

In a switch statement, the break statement causes the program to execute the next statement outside the switch statement. Without a break statement, every statement from the matched case label to the end of the switch statement, including the default clause, is executed.

In loops, the break statement ends execution of the nearest enclosing do, for, or while statement. Control passes to the statement that follows the ended statement, if any.

Within nested statements, the break statement ends only the do, for, switch, or while statement that immediately encloses it. You can use a return or goto statement to transfer control from more deeply nested structures.

Example

The following code shows how to use the break statement in a for loop.

#include <iostream>
using namespace std;

int main()
{
    // An example of a standard for loop
    for (int i = 1; i < 10; i++)
    {
        cout << i << '\n';
        if (i == 4)
            break;
    }

    // An example of a range-based for loop
int nums []{1, 2, 3, 4, 5, 6, 7, 8, 9, 10};

    for (int i : nums) {
        if (i == 4) {
            break;
        }
        cout << i << '\n';
    }
}
In each case: 
1
2
3

The following code shows how to use break in a while loop and a do loop.

#include <iostream>
using namespace std;

int main() {
    int i = 0;

    while (i < 10) {
        if (i == 4) {
            break;
        }
        cout << i << '\n';
        i++;
    }

    i = 0;
    do {
        if (i == 4) {
            break;
        }
        cout << i << '\n';
        i++;
    } while (i < 10);
}
In each case:
0
1
2
3

The following code shows how to use break in a switch statement. You must use break in every case if you want to handle each case separately; if you do not use break, the code execution falls through to the next case.

#include <iostream>
using namespace std;

enum Suit{ Diamonds, Hearts, Clubs, Spades };

int main() {

    Suit hand;
    . . .
    // Assume that some enum value is set for hand
    // In this example, each case is handled separately
    switch (hand)
    {
    case Diamonds:
        cout << "got Diamonds \n";
        break;
    case Hearts:
        cout << "got Hearts \n";
        break;
    case Clubs:
        cout << "got Clubs \n";
        break;
    case Spades:
        cout << "got Spades \n";
        break;
    default: 
          cout << "didn't get card \n";
    }
    // In this example, Diamonds and Hearts are handled one way, and
    // Clubs, Spades, and the default value are handled another way
    switch (hand)
    {
    case Diamonds:
    case Hearts:
        cout << "got a red card \n";
        break;
    case Clubs:
    case Spades: 
    default:
        cout << "didn't get a red card \n";
    }
}

See Also

Reference

Jump Statements (C++)

C++ Keywords

continue Statement (C++)