// Sample solution for http://www dot ferozeh.com slash Interviews slash misc slah imo.aspx

// try2: Read each file at most two times, at most two files open at a time.

// W = max_number_of_words_in_file, W0 = num_words_in_first_file, O(W0lgWO + lgW0 * Sum|W|)

// lazyboybd -= at =- gmail -= dot =- com

#include <iostream>

#include <stdio.h>

#include <stdlib.h>

#include <vector>

#include <stdlib.h>

#include <algorithm>

using namespace std;



#define rep(i, n) for (i = 0; i < (n); ++i)

#define is_char(x) (((x)>='a'&&(x)<='z')||((x)>='A'&&(x)<='Z'))



char* file_input[] = {

  "I am a bat, man how do You do testing far",

  "I am a cat walk man, How do you test it",

  "I am a very smashing man how do you do foo bar"//,

  //""

};



char* get_word(char** p, int* len) {

  while(**p && !is_char(**p)) ++(*p);

  if (!**p) return NULL;

  char* ret = *p;

  *len = 0;

  while(**p && is_char(**p)) ++(*p), ++(*len);

  // we're modifying input

  //**p = 0;

  return ret;

}



bool strnieq(char* a, char* b, int alen, int blen) {

  if (alen == blen) {

    while(alen--) {

      if (tolower(*a) != tolower(*b)) return false;

      a++, b++;

    }

    return true;

  }

  return false;

}

void print_word(char*p, int len) {

  while(len--) putchar(*p++);

}



// join "foo", "bar", "baz" to "foo-bar-baz", also mallocs.

char* word_up(char* a, int alen, char* b, int blen, char* c, int clen) {

  int len = alen + blen + clen + 3;

  char *ret = (char*) malloc(sizeof(char) * len);

  while(alen--) *ret++ = *a++; *ret++ = '-';

  while(blen--) *ret++ = *b++; *ret++ = '-';

  while(clen--) *ret++ = *c++; *ret++ = 0;

  return ret - len;

}



typedef pair<char*, int> entry;

bool ptr_cmp(const entry& a, const entry& b) {

  return stricmp(a.first, b.first) < 0;

}

bool not_found(const entry& a) {

  // A is moving

  if (a.second == false) {

    free(a.first);

  }

  return !a.second;

}

vector<entry>::iterator is_in_list(vector<entry>& v, const entry& e, char* w, bool& ret) {

  vector<entry>::iterator eit = lower_bound(v.begin(), v.end(), e, ptr_cmp);

  ret = eit != v.end() && !stricmp(eit->first, w);

  return eit;

}



bool find_and_set_word_in_vector(vector<entry>& v, char* wj0, int lenj0, char* wj1, int lenj1, char* wj2, int lenj2) {

  char* t = word_up(wj0, lenj0, wj1, lenj1, wj2, lenj2);

  entry tentry = make_pair(t, false);

  bool is_found;

  vector<entry>::iterator e = is_in_list(v, tentry, t, is_found);

  if (is_found) {

    e->second = true; // set it to found.

  }

  return is_found;

}



int try2(int n) {

  int i, j, k;



  vector<entry> master_list;

  // open file0

  char* p0 = file_input[0];

  int len0, len1, len2;

  char* w00 = get_word(&p0, &len0);

  char* w01 = get_word(&p0, &len1);

  char* w02 = get_word(&p0, &len2);

  while (w02 != NULL) {

    char* t = word_up(w00, len0, w01, len1, w02, len2);

    master_list.push_back(make_pair(t, false));

    // advance reading word in file0

    w00 = w01, w01 = w02; len0 = len1, len1 = len2;

    w02 = get_word(&p0, &len2);

  }

  sort(master_list.begin(), master_list.end(), ptr_cmp);

  //rep(i, master_list.size()) puts(master_list[i].first);



  rep(j, n) if (j > 0) {

    rep(i, master_list.size()) master_list[i].second = false;

    // open and read file j

    char* pj = file_input[j];

    int lenj0, lenj1, lenj2;

    char* wj0 = get_word(&pj, &lenj0);

    char* wj1 = get_word(&pj, &lenj1);

    char* wj2 = get_word(&pj, &lenj2);

    while (wj2 != NULL) {

      find_and_set_word_in_vector(master_list, wj0, lenj0, wj1, lenj1, wj2, lenj2);



      // advance reading word in filej

      wj0 = wj1, wj1 = wj2; lenj0 = lenj1, lenj1 = lenj2;

      wj2 = get_word(&pj, &lenj2);

    }

    // close file j



    // Filter out not found entries.

    vector<entry>::iterator last = remove_if(master_list.begin(), master_list.end(), not_found);

    master_list.resize(last - master_list.begin());

    //printf("After pass %d\n", j);

    //rep(i, master_list.size()) printf("%d: %s\n", i, master_list[i].first);

  }



  // now read the files again to remove stuffs.

  rep(j, n) {

    // open filej (except file0, which is still open)

    char* pj = file_input[j];

    int lenj0, lenj1, lenj2;

    char* wj0 = get_word(&pj, &lenj0);

    char* wj1 = get_word(&pj, &lenj1);

    char* wj2 = get_word(&pj, &lenj2);

    bool print0 = true, print1 = true, print2 = true;

    printf("File %d\nOriginal: %s\nOutpooot: ", j, file_input[j]);

    bool fir = true;

    while (wj2 != NULL) {

      bool found = find_and_set_word_in_vector(master_list, wj0, lenj0, wj1, lenj1, wj2, lenj2);

      if (!found) {

        // maybe print wj0

        if (print0) { if (fir) fir = 0; else printf(" "); print_word(wj0, lenj0); }

        print0 = print1; print1 = print2; print2 = true;

      }

      else {

        // we found match, set next two words to be not printed as well.

        print0 = false; print1 = false; print2 = true;

      }



      // advance reading word in filej

      wj0 = wj1, wj1 = wj2; lenj0 = lenj1, lenj1 = lenj2;

      wj2 = get_word(&pj, &lenj2);

    }

    if (wj0 != NULL && print0) { if (fir) fir = 0; else printf(" "); print_word(wj0, lenj0); }

    if (wj1 != NULL && print1) { if (fir) fir = 0; else printf(" "); print_word(wj1, lenj1); }

    printf("\n");

  }



  // close file0



  // clean up stuffs.

  rep(i, master_list.size()) free(master_list[i].first); master_list.clear();

  return 0;

}



int try1_naive(int n) {

  int i, j, k;

  char* p0 = file_input[0];

  

  int len0, len1, len2;

  char* w00 = get_word(&p0, &len0);

  char* w01 = get_word(&p0, &len1);

  char* w02 = get_word(&p0, &len2);



  char* w[55][3];

  int len[55][3];

  while(w02 != NULL) {

    rep(j, n) if (j > 0) {

      char f = false;

      char *pj = file_input[j];

      w[j][0] = get_word(&pj, &len[j][0]), w[j][1] = get_word(&pj, &len[j][1]), w[j][2] = get_word(&pj, &len[j][2]);

      while(w[j][2] != NULL) {

        if (strnieq(w00, w[j][0], len0, len[j][0]) && strnieq(w01, w[j][1], len1, len[j][1]) && strnieq(w02, w[j][2], len2, len[j][2])) {

          f = true; break;

        }

        w[j][0] = w[j][1], w[j][1] = w[j][2], len[j][0] = len[j][1], len[j][1] = len[j][2];

        w[j][2] = get_word(&pj, &len[j][2]);

      }

      if (!f) break;

    }



    if (j >= n) {

      // found w00, w01, w02

      print_word(w00, len0), putchar(' ');

      print_word(w01, len1), putchar(' ');

      print_word(w02, len2); putchar('\n');

    }



    // advance reading word in file0

    w00 = w01, w01 = w02; len0 = len1, len1 = len2;

    w02 = get_word(&p0, &len2);

  }



  return 0;

}



int main() {

  int n = sizeof(file_input)/sizeof(file_input[0]);

  printf("Num files: %d\n", n);

  //try1_naive(n);

  try2(n);

  return 0;

}