cws/cw04.tex
changeset 111 cd6b9fe4bce5
parent 110 62389faa66e4
child 218 22705d22c105
equal deleted inserted replaced
110:62389faa66e4 111:cd6b9fe4bce5
   139 \item Repeatable roman digits are $I$, $X$, $C$ and $M$. The other ones
   139 \item Repeatable roman digits are $I$, $X$, $C$ and $M$. The other ones
   140   are non-repeatable. Repeatable digits can be repeated upto 3 times in a
   140   are non-repeatable. Repeatable digits can be repeated upto 3 times in a
   141   number (for example $MMM$ is OK); non-repeatable digits cannot be
   141   number (for example $MMM$ is OK); non-repeatable digits cannot be
   142   repeated at all (for example $VV$ is excluded).
   142   repeated at all (for example $VV$ is excluded).
   143   
   143   
   144 \item If a smaller digits precedes a bigger digit, then $I$ can precede $V$ and $C$; $X$ can preced
   144 \item If a smaller digits precedes a bigger digit, then $I$ can precede $V$ and $X$; $X$ can preced
   145   $L$ and $C$; and $C$ can preced $D$ and $M$. No other combination is permitted in this case.
   145   $L$ and $C$; and $C$ can preced $D$ and $M$. No other combination is permitted in this case.
   146 
   146 
   147 \item If a smaller digit precedes a bigger digit (for example $IV$), then the smaller number   
   147 \item If a smaller digit precedes a bigger digit (for example $IV$), then the smaller number   
   148   must be either the first digit in the number, or follow a digit which is at least 10 times its value.
   148   must be either the first digit in the number, or follow a digit which is at least 10 times its value.
   149   So $VIV$ is excluded, because $I$ follows $V$ and $I * 10$ is bigger than $V$; but $XIV$ is
   149   So $VIV$ is excluded, because $I$ follows $V$ and $I * 10$ is bigger than $V$; but $XIV$ is