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 `` and " 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which converts text containing double-quote (") characters into text that is identical except that double-quotes have been replaced by the two-character sequences required by TeX for delimiting quotations with oriented double-quotes.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 and Output
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. The text must be output exactly as it was input except that:
- the first"in each pair is replaced by two`characters:``and
- the second"in each pair is replaced by two'characters:''.
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 to `C', 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. To `C' or not to `C', that is The Question!''
#define RUN #ifdef RUN #include <stdio.h> int main() { int c, q = 1; while((c= getchar()) != EOF) { if(c == '"') { printf("%s", q ? "``" : "''"); q = !q; } else printf("%c", c); } return 0; } #endif