break statement

Causes the enclosing 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

Appears only within the statement of a loop body (while, do-while, for) or within the statement of a switch.

Explanation

After this statement the control is transferred to the statement or declaration immediately following the enclosing loop or switch, as if by goto.

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

#include <stdio.h>
 
int main(void)
{
    int i = 2;
    switch (i) {
        case 1: printf("1");
        case 2: printf("2");   // i==2, so execution starts at this case label
        case 3: printf("3");
        case 4:
        case 5: printf("45");
                break;         // execution of subsequent cases is terminated
        case 6: printf("6");
    }
    printf("\n");
 
    // Compare outputs from these two nested for loops.
    for (int j = 0; j < 2; j++) 
        for (int k = 0; k < 5; k++) 
            printf("%d%d ", j,k);
    printf("\n");
    for (int j = 0; j < 2; j++) {
        for (int k = 0; k < 5; k++) { // only this loop is exited by break
            if (k == 2) break;
            printf("%d%d ", j,k);
        }
    }
}

2345
00 01 02 03 04 10 11 12 13 14 
00 01 10 11

References

• C17 standard (ISO/IEC 9899:2018):
• 6.8.6.3 The break statement (p: 111)
• C11 standard (ISO/IEC 9899:2011):
• 6.8.6.3 The break statement (p: 153)
• C99 standard (ISO/IEC 9899:1999):
• 6.8.6.3 The break statement (p: 138)
• C89/C90 standard (ISO/IEC 9899:1990):
• 3.6.6.3 The break statement

See also