Does the break statement break out of multiple loops?

Question

If I have a while loop (a) inside another while loop (b) and I use the break statement while in the 'b' loop, does it also break out of the 'a' loop or do I stay in the 'a' loop?

Answer 1

break; only breaks from the innermost loop or switch body it appears in.

If you intend to break from nested loops, you might consider moving the nested loops to a separate function and using return to exit the function from any point inside its body.

Example:

    ...
    int matrix[ROWS][COLS];
    int value;
    ...
    int found = 0;
    for (int row = 0; row < ROWS; row++) {
        for (int col = 0; col < COLS; col++) {
            if (matrix[row][col] == value) {
                found = 1;
                break;
            }
        }
        if (found)
            break;
    }
    ...

Can be simplified as:

int hasvalue(int matrix[ROWS][COLS], int value) {
    for (int row = 0; row < ROWS; row++) {
        for (int col = 0; col < COLS; col++) {
            if (matrix[row][col] == value)
                return 1;
        }
    }
    return 0;
}

    ...
    int matrix[ROWS][COLS];
    int value;
    ...
    found = hasvalue(matrix, value);
    ...