Can `goto` Help Exit Multiple Nested Loops When `break` Fails?

Exiting Multiple Nested Loops with Break

While nesting multiple 'for' loops is a common approach for iterating over data structures, prematurely exiting all the loops can sometimes be necessary. Can we utilize the 'break' function for this purpose?

The Limitations of 'break'

Unfortunately, the 'break' function operates within the scope of its immediate loop. Applying it to break out of multiple nested loops is not effective. Attempting to do so simply terminates the current loop, leaving the nested loops unaffected.

The Case for 'goto'

Ironically, the trusty 'goto' statement, often frowned upon in modern programming practices, emerges as the appropriate solution for this specific scenario. Unlike 'break', 'goto' allows for jumping between code blocks regardless of their nesting level.

Controlling the Loop Exit Depth

Controlling the number of loops exited using 'goto' involves labeling the loops and specifying the appropriate label as the 'goto' destination. For instance, to exit two nested loops:

outer_loop:
  for (initialization1; condition1; increment1) {
    inner_loop:
      for (initialization2; condition2; increment2) {
        // Exit both loops
        if (condition) {
          goto outer_loop;
        }
      }
  }

By jumping to the label associated with the outermost loop, both nested loops terminate immediately.

Thus, while 'break' is unsuitable for exiting multiple nested loops, 'goto' provides the necessary functionality, albeit with a less graceful syntax.

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