#include <iostream>
#include <vector>
#include <utility>
#include <string>
#include <boost/assign/std/vector.hpp>
#include <cassert>
#include <cmath>

using namespace std;
using namespace boost::assign;


double
isupper_f(string s)
{
  if ( isupper(s[0]) ) return 0;
  return 1;
}

double
len_f(string s)
{
  return s.size();
}

double
dotprod(vector<double> a, vector<double> b)
{
  assert(a.size() == b.size());
  double sum;
  for (size_t i = 0; i < a.size(); i++) {
    sum += a[i] * b[i];
  }
  return sum;
}

vector<double>
vadd(double x, vector<double> v)
{
  for (size_t i = 0; i < v.size(); i++) {
    v[i] += x;
  }
  return v;
}

vector<double>
vadd(vector<double> v, vector<double> w)
{
  assert(v.size() == w.size());
  for (size_t i = 0; i < v.size(); i++) {
    v[i] += w[i];
  }
  return v;
}

vector<double>
vsub(vector<double> v, vector<double> w)
{
  assert(v.size() == w.size());
  for (size_t i = 0; i < v.size(); i++) {
    v[i] -= w[i];
  }
  return v;
}

vector<double>
vmult(double x, vector<double> v)
{
  for (size_t i = 0; i < v.size(); i++) {
    v[i] *= x;
  }
  return v;
}

double
vlen(vector<double> v)
{
  return sqrt(dotprod(v, v));
}

vector<double>
vnorm(vector<double> v)
{
  double len = vlen(v);
  for (size_t i = 0; i < v.size(); i++) {
    v[i] /= len;
  }
  return v;
}


int main(void)
{
  vector<double> classes;
  vector<string> words;
  classes += -1.,     1.,      -1.,      1.,       -1.,    1.,      -1.,     1.,         -1.,     1.;
  words   += "Haus","house","Mauer","plant","Zeug","hello","Maus","worker","Quartz","point";

  vector<pair<double, string> > examples;
  for (size_t i = 0; i < classes.size(); i++) {
    pair<double, string> p;
    p.first = classes[i];
    p.second = words[i];
    examples.push_back(p);
  }

  vector<double> weights;
  weights += 0.,0.;

  double eta = 0.5;
  double bias = 0.;
  
  for (size_t t = 0; t < 2; t++)
  {
    for (size_t x = 0; x < examples.size(); x++) {
      vector<double> feats;
      feats += isupper_f(examples[x].second), len_f(examples[x].second);
      double err = dotprod(weights, feats);
      //if ( (examples[x].first == 1 && err < 0) || (examples[x].first == -1 && err >= 0) ) {
      if ( examples[x].first  * (err + bias) <= 0 ) {
        weights = vadd(weights, vmult(examples[x].first*eta, feats));
        bias += examples[x].first*eta; 
      }
      cout << "w " << weights[0] << " " << weights[1] << " bias " << bias << endl;
    }
    cout << "--" << endl;
  }
  
   cout << endl;
   for (size_t x = 0; x < examples.size(); x++) {
      vector<double> feats;
      feats += isupper_f(examples[x].second), len_f(examples[x].second);
      cout << dotprod(weights, feats) + bias << endl;
    }
    
    vector<double> f;
    f += isupper_f("Bauer"), len_f("Bauer");
    cout << "test: " << dotprod(weights, f) + bias << endl;


  return 0;
}