symtab complete

symtab.c

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>

#define SYMTAB_SIZE 100
#define SYMBOL_SIZE 30

typedef unsigned int uint;

typedef struct{
	char sym[SYMBOL_SIZE];
	int loc;
}Symbol;


Symbol symtab[SYMTAB_SIZE];

uint hash_str(char* str){
	uint hash = 0;
	uint n,i;

	for(i = 0; str[i]; i++){
	  str[i] = tolower(str[i]);
	}


	for(i=0;*(str+i) != '\0';++i){
		if(isalpha(*(str+i)))
			n = *(str+i) - 'a' + 1;
		else
			n = 27;
		hash = ((hash << 3) + n) % SYMTAB_SIZE;
	}

	return hash;
}


void initialize_symtab(){
	int i;
	for(i=0;i<SYMTAB_SIZE;++i){
		symtab[i].sym[0] = '\0';
		symtab[i].loc = -1;
	}
}

void insert_to_symtab(char* sym,int loc){
	int hash = hash_str(sym);
	strcpy(symtab[hash].sym,sym);
	symtab[hash].loc=loc;
}

Symbol get_symbol(char* sym){
	return symtab[hash_str(sym)];
}



int main(void){
	int c,loc;
	char sym[SYMBOL_SIZE];
	Symbol s;
	initialize_symtab();

	do{
		printf("1. Add a Symbol\n");
		printf("2. Look up a Symbol\n");
		printf("3. Quit\n");
		scanf("%d",&c);

		switch(c){
			case 1:{
				printf("Enter Symbol name:");
				scanf("%s",sym);
				printf("Enter Symbol location:");
				scanf("%d",&loc);
				insert_to_symtab(sym,loc);
				break;
			}

			case 2:{
				printf("Enter Symbol name:");
				scanf("%s",sym);
				s = get_symbol(sym);
				if(s.loc == -1)
					printf("Symbol not found!\n");
				else
					printf("Symbol found!\nName: %s\nLocation: %d\n",s.sym,s.loc);
				break;
			}
		}
	}while(c != 3);

	return 0;
}