/*--------------------------------------------------------------------*/ 
/*  Problem chapter6_23                                               */ 
/*                                                                    */ 
/*  This program reads a data file and determines the number of       */ 
/*  occurances of each character in the file.  It then prints the     */ 
/*  characters and the number of times that they occurred.            */ 
/*--------------------------------------------------------------------*/ 

#include <iostream> 
#include <string> 
#include <fstream> 
using namespace std; 
 
int main() 
{    
   /*  Declare variables.  */    
   int occur[128], i;    
   char c;    
   ifstream fin; 
   string filename;
 
   /*  Open input file.  */    
   cout << "Enter name of input file: ";
   cin >> filename;
   fin.open(filename.c_str() );
   if(fin.fail())
   {
      cerr << "error opening file " << filename << endl;
      exit(1);
   }

   /*  Initialize array. */     
   for (i = 0; i<128; i++)	 
      occur[i] = 0;  
   /* Set the array to be 0 */
 
   /*  Count characters  */    
   fin.get(c);
   while( !fin.eof() )    
      {
      occur[(int)c]++;    
      fin.get(c);
      }
 
   /*  Output the results.  */ 
   for (i = 0; i<128; i++)	 
    {  if (occur[i] != 0)	    
           cout << "Character " << (char)i   
        	<< "  OCCURANCES: " << occur[i] << endl; 
    }
 
   fin.close();
   /*  Exit program.  */    
   return 0; 
}