All if, while, for, do and switch statements should be followed by a brace-enclosed compound statement.

If only indentation is used to indicate that a single statement belongs to an "if", "while" or "for", it is a frequently occurring mistake to enhance this construct by adding another statement without supplying the now necessary {..} to indicate that both statements belong to the while. The practice of using {..} also aids readability.

Example:

  while( ... ) i++;   /* WRONG */ 

  while( ... )
  {
    i++;   /* RIGHT */
  }

Example:

  for(...) i++; /* WRONG */

  for(...)
  {
    i++; /* RIGHT */
  }

Example:

  if ( ... ); /* WRONG, no {} */

  if ( ... )
  {
    /* EMPTY*/ /* RIGHT */
  }