break statement

 

C++

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Technical Specifications

 

C++ language

 

Statements

Labels

label : statement

Expression statements

expression ;

Compound statements

{ statement... }

Selection statements

if

switch

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while

do-while

for

range for(C++11)

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break

continue

return

goto

Declaration statements

declaration ;

Try blocks

try compound-statement handler-sequence

 

Causes the enclosing for, range-for, while or do-while loop or switch statement to terminate.

Used when it is otherwise awkward to terminate the loop using the condition expression and conditional statements.

Syntax

attr(optional) break ;

Explanation

After this statement the control is transferred to the statement immediately following the enclosing loop or switch. As with any block exist, all automatic storage objects declared in enclosing compound statement or in the condition of a loop/switch are destroyed, in reverse order of construction, before the execution of the first line following the enclosing loop.

Keywords

break

Notes

A break statement cannot be used to break out of multiple nested loops. The goto statement may be used for this purpose.

Example

Run this code

#include <iostream>
 
int main()
{
    int i = 2;
    switch (i) {
        case 1: std::cout << "1";
        case 2: std::cout << "2";   //execution starts at this case label
        case 3: std::cout << "3";
        case 4:
        case 5: std::cout << "45";
                break;              //execution of subsequent statements is terminated
        case 6: std::cout << "6";
    }
 
    std::cout << '\n';
 
    for (int j = 0; j < 2; j++) {
        for (int k = 0; k < 5; k++) {         //only this loop is affected by break
            if (k == 2) break;
            std::cout << j << k << " ";
        }
    }
}

Output:

2345
00 01 10 11

See also

C documentation for break