Think: 引號轉換題，　因為不知道長度，所以用getchar（） 但是不明白　為什么代碼　在編譯器上會　報錯。。。 但是　提交是ＡＣ的。。 所以思路就是，讀取字符然后判斷時候是 ” ，　如果是的話在判斷 是第幾次出現（也就是判斷　是左　還是　右　引號），然后　改變 輸出字符。 題目雖然很長　但是是水題　。。。

PRoblem Description TEX is a typesetting language developed by Donald Knuth. It takes source text together with a few typesetting instructions and produces, one hopes, a beautiful document. Beautiful documents use double-left-quote and double-right-quote to delimit quotations, rather than the mundane ” which is what is provided by most keyboards. Keyboards typically do not have an oriented double-quote, but they do have a left-single-quote and a right-single-quote '. Check your keyboard now to locate the left-single-quote key (sometimes called the “backquote key”) and the right-single-quote key ’ (sometimes called the “apostrophe” or just “quote”). Be careful not to confuse the left-single-quote ` with the “backslash” key . TEX lets the user type two left-single-quotes “ to create a left-double-quote and two right-single-quotes ” to create a right-double-quote. Most typists, however, are accustomed to delimiting their quotations with the un-oriented double-quote “.

If the source contained “To be or not to be,” quoth the bard, “that is the question.” then the typeset document produced by TEX would not contain the desired form: “To be or not to be,” quoth the bard, “that is the question.” In order to produce the desired form, the source file must contain the sequence: To be or not to be,'' quoth the bard,that is the question.” You are to write a program which converts text containing double-quote (“) characters into text that is identical except that double-quotes have been replaced by the two-character sequences required by TEX for delimiting quotations with oriented double-quotes. The double-quote (“) characters should be replaced appropriately by either if the " opens a quotation and by '' if the " closes a quotation. Notice that the question of nested quotations does not arise: The first " must be replaced by, the next by ”, the next by , the next by '', the next by, the next by ”, and so on.

Input Input will consist of several lines of text containing an even number of double-quote (“) characters. Input is ended with an end-of-file character.

Output The text must be output exactly as it was input except that:

Sample Input

“To be or not to be,” quoth the Bard, “that is the question”. The programming contestant replied: “I must disagree. To C' or not toC’, that is The Question!”

Sample Output

To be or not to be,'' quoth the Bard,that is the question”. The programming contestant replied: `I must disagree. ToC’ or not to `C’, that is The Question!”

題目大意： １．給定字符串 ２．將左”轉換成“　將右”轉換成’ ‘;