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// -*- mode: c++ -*-// $Id: hash.g++,v 1.2 2001/06/20 03:20:02 doug Exp $// http://www.bagley.org/~doug/shootout/#include <ctime>#include <cstdlib>#include <string.h>#include <stdio.h>#include <iostream>#include <tr1/unordered_map>using namespace std;using namespace std::tr1;struct eqstr {    bool operator()(const char* s1, const char* s2) const {		return strcmp(s1, s2) == 0;    }};namespace std {	namespace tr1 {		template<>		struct hash<const char*> {			std::size_t	operator()(const char* s) const {				return _Fnv_hash<>::hash(s, strlen(s));			}		};	}}int main(int argc, char *argv[]) {    int n = ((argc == 2) ? atoi(argv[1]) : 1);    clock_t start=clock();    char buf[16];		typedef unordered_map<const char*, int, hash<const char*>, eqstr> HM;	    HM X(n);    for (int i=1; i<=n; i++) {		sprintf(buf, "%x", i);		X.insert( make_pair(strdup(buf), i) );    }    int c = 0;    for (int i=n; i>0; i--) {		sprintf(buf, "%d", i);		if (X.find(buf)!=X.end())			c++;    }	cout << c << endl;  clock_t endt=clock();   std::cout <<"Time: " << double(endt-start)/CLOCKS_PER_SEC * 1000 << " ms\n";}