TEX Quotes—字符串

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that is identical except that double-quotes have been replaced by the two-character sequences required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
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:
• 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!''

分析：循环读入，依次判断，使用三目运算符进行二次判断；

#include<bits/stdc++.h>
using namespace std;
int main(){
bool temp=true;
char c;
while((c=getchar())!=EOF){
	if(c=='"')	{
		cout<<(temp?"``":"''"); 
		temp=!temp;
	}
	else cout<<c;
}
return 0;
}