/* The following code example is taken from the book
* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
#include <iostream>
#include <iomanip>
#include <map>
#include <string>
#include <algorithm>
using namespace std;
/* function object to compare strings
* - allows you to set the comparison criterion at runtime
* - allows you to compare case insensitive
*/
class RuntimeStringCmp {
public:
// constants for the comparison criterion
enum cmp_mode {normal, nocase};
private:
// actual comparison mode
const cmp_mode mode;
// auxiliary function to compare case insensitive
static bool nocase_compare (char c1, char c2)
{
return toupper(c1) < toupper(c2);
}
public:
// constructor: initializes the comparison criterion
RuntimeStringCmp (cmp_mode m=normal) : mode(m) {
}
// the comparison
bool operator() (const string& s1, const string& s2) const {
if (mode == normal) {
return s1<s2;
}
else {
return lexicographical_compare (s1.begin(), s1.end(),
s2.begin(), s2.end(),
nocase_compare);
}
}
};
/* container type:
* - map with
* - string keys
* - string values
* - the special comparison object type
*/
typedef map<string,string,RuntimeStringCmp> StringStringMap;
// function that fills and prints such containers
void fillAndPrint(StringStringMap& coll);
int main()
{
// create a container with the default comparison criterion
StringStringMap coll1;
fillAndPrint(coll1);
// create an object for case-insensitive comparisons
RuntimeStringCmp ignorecase(RuntimeStringCmp::nocase);
// create a container with the case-insensitive comparisons criterion
StringStringMap coll2(ignorecase);
fillAndPrint(coll2);
}
void fillAndPrint(StringStringMap& coll)
{
// fill insert elements in random order
coll["Deutschland"] = "Germany";
coll["deutsch"] = "German";
coll["Haken"] = "snag";
coll["arbeiten"] = "work";
coll["Hund"] = "dog";
coll["gehen"] = "go";
coll["Unternehmen"] = "enterprise";
coll["unternehmen"] = "undertake";
coll["gehen"] = "walk";
coll["Bestatter"] = "undertaker";
// print elements
StringStringMap::iterator pos;
cout.setf(ios::left, ios::adjustfield);
for (pos=coll.begin(); pos!=coll.end(); ++pos) {
cout << setw(15) << pos->first.c_str() << " "
<< pos->second << endl;
}
cout << endl;
}
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