#include <stdio.h>
#include <conio.h>
#include <string.h>
#include <stdlib.h>
#define LEN 100

typedef char string;
void FindSimillar(string FirstFile, string SecondFile, int vec);
void FindDifference(string FirstFile, string SecondFile, int vec);
void Add(string NewFile, string FirstFile, string SecondFile);
int ShowMenu (void);
void main(void)
{
	string		str1;
	string		str2;
	string      Main;
	int			vec;
	int			index = 0;
	int			menu  = 1;
	  while (menu)
	  {
    system("cls"); 
    menu = ShowMenu();
    switch (menu)
    {
	case 1:
	printf("enter the first path: ");
	scanf("%s",str1);
	printf("enter the second path: ");
	scanf("s",str2);
    
	FindSimillar(str1, str2,vec);//activates thr function
	while (vec!=-1)//until the end of the vec
		{
		printf("line %d.",vec);//prints
		}
		
	printf ("\nDone.");
	break;
	case 2:
	printf("enter the first path: ");
	gets(str1);
	printf("enter the second path: ");
	gets(str2);
    
	FindDifference(str1, str2, vec);//activates the functuin
		while (vec!=-1)//until the end of the vec
		{
		printf("line %d.",vec);//prints
		}
		
	printf ("\nDone.");
	break;
	case 3:
	printf("enter the new file's path: ");
	gets(Main);
	printf("enter the first file's path: ");
	gets(str1);
	
	printf("enter the second file's path: ");
	gets(str2);
    
		Add(Main, str1, str2);//activates the function
		printf ("\nDone.");
	break;
	case 4:
	printf ("\nexiting...");
	break;
      default:
	printf ("\nEnter 1-4");
    }
    getch();
  }
}
//---------------------------------------------------------------------------------------------------------------------
void FindSimillar(string FirstFile, string SecondFile, int vec)
{
	FILE		*cmpr1;
	FILE		*cmpr2;
	int			line=0;
	int			index=0;
	string		ff;//first string
	string		sf;//second string
	cmpr1 = fopen (FirstFile,"rt");
	cmpr2 = fopen (SecondFile,"rt");
	
	while ((!feof(cmpr1)) && (!feof(cmpr2)))//while its not the end of any of the files
	{
		fgets (ff, LEN, cmpr1);//get the line/string
		fgets (sf, LEN, cmpr2);//get the line/string
		line++;
		if (strcmp (ff, sf)==0)//if they're equal
		{
			vec=line;//puts in the vector the line's number
			index++;
		}
	  
	}
	vec=-1;//a sign to recoginize the end of file
	
	fclose (cmpr1);
	fclose (cmpr2);

}
//---------------------------------------------------------------------------------------------------------------------
void FindDifference(string FirstFile, string SecondFile, int vec)
{
	FILE		*cmpr1;
	FILE		*cmpr2;
	int			line=0;
	int			index=0;
	string		ff;//first string
	string		sf;//second string
	cmpr1 = fopen (FirstFile,"rt");
	cmpr2 = fopen (SecondFile,"rt");
	
	while ((!feof(cmpr1)) && (!feof(cmpr2)))
	{
		fgets (ff, LEN, cmpr1);//gets the line/string
		fgets (sf, LEN, cmpr2);//gets the line/string
		line++;
		if (strcmp (ff, sf))//if they're different
		{
			vec=line;//puts the line's number
			index++;
		}
	  
	}
	vec=-1;
	
	fclose (cmpr1);
	fclose (cmpr2);

}
//----------------------------------------------------------------------------------------------------------------------
void Add(string NewFile, string FirstFile, string SecondFile)
{
  FILE *New; // a pointer to the source file.
  FILE *First;
  FILE *Sec; // a pointer to the target file.
  string file; // a row to save lines from the source file.
  New   = fopen (NewFile, "at");
  First = fopen (FirstFile,"rt");
  Sec   = fopen (SecondFile,"rt");
  if ((!New) || (!First) || (!Sec))
  {
    exit (1);
  }
  // process
  while (fgets (file, 100, First))
  {
    fputs (file, New);
  }
   while (fgets (file, 100, Sec))
  {
    fputs (file, New);
  }
  // closing files
  fclose (New);
  fclose (First);
  fclose (Sec);
}

//----------------------------------------------------------------------------------------------------------------------
 int ShowMenu (void)
{
  // variable definition
   int menu;
  // code section
  // menu printing
  printf ("***Menu***\n");
  printf ("1. compare one file to another and finds the lines which are simillar\n");
  printf ("2. compare one file to another and finds the lines which are different\n");
  printf ("3. Adding to a new file - two others files\n");
  printf ("0. exit\n");
  // choise input
  printf ("Please enter your choise now 1-3 (Exit - 0): ");
  scanf ("%d", &menu);
  printf ("\n");
  
  return menu;
}