Category ArchiveCode
C++ 31 Jan 2010 11:35 pm
Snippet: Custom Type to Output Stream
//tinodidriksen.com/uploads/code/cpp/custom-to-ostream.cpp
#include <ostream> #include <iostream> #include <string> struct Custom { std::string m_str; friend std::ostream& operator<<(std::ostream& stm, const Custom& obj); }; std::ostream& operator<<(std::ostream& stm, const Custom& obj) { stm << obj.m_str; return stm; } int main() { Custom cst; cst.m_str = "waffles"; std::cout << cst << std::endl; }
C++ 31 Jan 2010 11:31 pm
Snippet: Convert String to Hex
//tinodidriksen.com/uploads/code/cpp/string-to-hex.cpp
#include <string> #include <sstream> #include <iostream> #include <iomanip> int main() { std::string str("abcABC123\xff\x01"); std::stringstream ss; for (size_t i=0 ; i<str.length() ; ++i) { ss << std::setw(2) << std::setfill('0') << std::hex << (int(str[i])&0xFF); } std::cout << ss.str(); }
C 31 Jan 2010 11:29 pm
Snippet: Convert Hex to Text
//tinodidriksen.com/uploads/code/c/hex-to-text.c
#include <stdlib.h> #include <stdio.h> #include <string.h> int main() { char buf[] = "54657374"; size_t len = strlen(buf); if (len & 1) { printf("Cannot take hex from odd length string.\n"); exit(1); } char *result = (char*)malloc(len/2 + 1); memset(result, 0, len/2 + 1); for (size_t i = 0 ; i < len/2 ; ++i) { char tmp[3] = {buf[i*2], buf[i*2+1], 0}; result[i] = (char)strtol(tmp, NULL, 16); } printf("%s converted to %s\n", buf, result); free(result); return 0; }
C++ 31 Jan 2010 11:23 pm
Snippet: Pointer Usage: Polymorphism
//tinodidriksen.com/uploads/code/cpp/pointer-polymorphism.cpp
#include <iostream> struct A { virtual void foo() { std::cout << "A::foo()" << std::endl; } virtual ~A() { } }; struct B : public A { void foo() { std::cout << "B::foo()" << std::endl; } }; int main() { A *a = new A; a->foo(); delete a; a = new B; a->foo(); delete a; }
C++ 04 Oct 2009 03:21 pm
C++ Map Speeds, MSVC++ Edition
(There is also a GNU g++ Edition of these performance tests, and a newer std::set comparison.)
Here is a complete test of MSVC++ map speeds, using same code as my previous map speed test: timemap.cpp with cycle.h.
The compilers are Microsoft Visual C++ 2008 Express as VC9 and Microsoft Visual C++ 2010 Beta as VC10. The containers are std::map, stdext::hash_map, std::tr1::unordered_map, and boost::unordered_map, each with _SECURE_SCL enabled and disabled.
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