#include<stdio.h>
#include<conio.h>
#define HASH_SIZE 10

int findkey(int );
void main()
{
unsigned int hash[HASH_SIZE][HASH_SIZE+1];
for(int i=0; i<HASH_SIZE; i++)
	{	hash[i][0]=0;	} //init the 1st col
int key;
int a,b,c;
clrscr();
puts("Enter a NEGATIVE number to stop entering the nos. ");
puts("Enter the Numbers ... ");
while(1)
	{
	scanf("%d", &a);
	if(a < 0)	{	break;	}
	key = findkey(a);
	hash[key][0]+=1;
	b=hash[key][0]; // hash[][0] is no of ele in hash[]
	if(b > HASH_SIZE)
		{
		printf("Key %d overflow..",key);
		continue;
		}
	hash[key][b] = a; //store in hash table
	}

puts("\nThe Hash Table is: ....");
for(int j=0; j<HASH_SIZE; j++)
	{
	printf("\nKey: %2d",j);
	for(int i=1; i< hash[j][0]+1; i++)
		{
		printf("%6d",hash[j][i]);
		}
	}
while(!kbhit());
}

int findkey(int i)
{
int sum=0;
while( (i/10)!=0)
	{
	sum=0;
	while(i!=0)
		{
		sum += i%10;
		i /= 10;
		}
	i=sum;
	}
return i;
}
/* HASH FUNCTION IS THE SUCESSIVE SUM OF DIGITS OF A NO.
TILL THE SUM IS A SINGLE DIGIT NUMBER, WHICH IS USED AS
THE KEY.  eg: 24221 ==> 11 ====> 2
			|	    ||	   |
			 - SUM --  --SUM--
*/