Template Hell

Man, When I first saw pointers, referencing and de-referencing and all, I thought that I had seen the worst that C++ can throw at you. And now come and greet the new enemy that I found

TEMPLATES!!!

So you think you know what templates do ? Lets see, they are a type of metaprogramming right ? They allow you to use C++ compiler as an interpreter and write generic code with the use of which C++ compiler would generate specific code. So that is what templates does ? Nope. Sorry but I thought so too. But along comes this code snippet which supposedly implements a while loop. Go figure! And when you do please tell me too :D

template

class loop {

private: enum { go = (I-1) != 0 };

public: static inline void f() {

// Whatever needs to go here

loop::f(); }

};

class loop<0> {

public:

static inline void f()

{ }

};

loop::f();

Jamming On

Well this time around I guess I might have some time to go after the code jam contest. Took some small steps in that way and here is the first result. Think I would use C++ for the contest. I would love to experiment with Python and use some C# or Java for this. I would love the java libraries in the more complex problems. But seems I can make do with C++ this while and this would be a good time as any to get those rusty C++ skills honed in. So here goes nothing. :D

This is my solution for the first practise problem. This is really cool, at least for me and I hope is good and correct C++. No C stdio, no c-strings and bettter still no mallocs. Take a look and see what comes.

/*

* main.cpp

*

* Created on: 27 Jul 2009

* Author: Osada

*/

#include

#include

#include

#include "math.h"

using namespace std;

void process(fstream *input_file, fstream *output_file, int line_no)

{

string num_str;

string source_lang;

string target_lang;

string convert_num_str;

char input_char = '\0';

(*input_file) >> num_str >> source_lang >> target_lang;

cout << "The number string is " <<>

cout <<>

cout <<>

/* Data processing variables set */

long target_lang_dim = target_lang.size();

long source_lang_dim = source_lang.size();

long source_lang_value = 0;

long pos_value = 0;

long convert_residue = 0;

std::reverse(num_str.begin(), num_str.end());

for(int i =0; i <>

{

pos_value = source_lang.find(num_str.at(i), 0);

source_lang_value += pos_value * powl(source_lang_dim, i);

}

convert_residue = source_lang_value;

ldiv_t div_result;

while(convert_residue != 0)

{

div_result = div(convert_residue, target_lang_dim);

convert_residue = div_result.quot;

convert_num_str.push_back(target_lang.at(div_result.rem));

}

std::reverse(convert_num_str.begin(), convert_num_str.end());

(*output_file) << "Case #" <<>

}

int main (int argc, char **argv)

{

/* File input variables */

fstream input_file("A-large-practice.in", fstream::in);

fstream output_file("output.txt", fstream::out);

int no_of_lines = 0;

input_file >> no_of_lines;

for(int i = 0; i

{

process(&input_file, &output_file, (i + 1));

}

input_file.close();

output_file.close();

}