Design a hash table to store phone #s. Your job is to write a hash function that has a parameter username, and generate a key. Username is unique, length 5 and can be A-Z, 0-9, space. Write a hash function that generate keys without collisions and use minimum memory.

let's try to understand problem:

code to generate hash function:

#include <stdio.h> 
#include <math.h> 
char arr[100];
int i,j=4,total=0;
double x;
/* this function will generate hashcode */
void hashcode()
{
 for(i=0;i<5;i++)
 {
  if(arr[i]==' ')  // to caovert space to 0
   x=0;
  
  if(arr[i]>='0'&& arr[i]<='9')  // to convert ascii of 0-9 to 1-10
   x=(arr[i]-47);

  if(arr[i]>='A'&& arr[i]<='Z') // to convert ascii of A-Z to 11-36
   x=(arr[i]-54);
  
  x=x*pow(37, j);     
  total=total+(int)x; 
  j--;      
 } 
}
int main() 
{
 printf("enter the usename of length 5\n");
 for(i=0;i<5;i++)
  scanf("%c",&arr[i]);
 hashcode();
 printf("\n%d",total);
 return 0;
}

output:-

enter the usename of length 5
Z10 A

67572482
----------------------------------------------
Z10 A=36*37^(4)+2*37^(3)+1*37^(2)+0*37^(1)+11*37^(0)

refer table givien below

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