Need help with homework:

How to utilize strdup()? What does it do?

A) In Insert(), you MUST "strdup() the character string, otherwise you will get weird results.

B) Create a symbtab.h files which exposes the Insert() and Search() and struct{} definition and include " symbtab.h" it in your *.c file

/**************************************************************************************************************************************************/

#include

#include

#include

#include

struct SymbTab {

char *symbol;

int address;

struct SymbTab *next;

};

struct SymbTab *first, *last;

int size = 0;

struct SymbTab *Insert(char *symbol, int address) {

struct SymbTab *p = first;

while (p != NULL) {

if (strcmp(p->symbol, symbol) == 0) {

printf("Error: symbol already present ");

exit(1);

}

p = p->next;

}

p = malloc(sizeof(struct SymbTab));

p->symbol = symbol;

p->address = address;

p->next = NULL;

if (size == 0) {

first = p;

last = p;

} else {

last->next = p;

last = p;

}

size++;

return p;

}

struct SymbTab *Search(char *symbol) {

struct SymbTab *p = first;

while (p != NULL) {

if (strcmp(p->symbol, symbol) == 0) {

return p;

}

p = p->next;

}

return NULL;

}

void Display() {

int i;

struct SymbTab *p;

p = first;

printf(" SYMBOL\tADDRESS ");

for (i = 0; i < size; i++) {

printf("%s\t%d ", p->symbol, p->address);

p = p->next;

}

}

void main() {

int op;

char la[10];

do {

printf(" SYMBOL TABLE IMPLEMENTATION ");

printf(" 1.INSERT 2.DISPLAY 3.SEARCH 4.END ");

printf(" Enter your option: ");

scanf("%d", &op);

switch (op) {

case 1:

printf(" Enter the symbol: ");

scanf("%s", la);

int address;

printf("Enter the address: ");

scanf("%d", &address);

Insert(la, address);

printf(" Symbol inserted ");

break;

case 2:

Display();

break;

case 3:

printf(" Enter the symbol to be searched: ");

scanf("%s", la);

struct SymbTab *result = Search(la);

printf(" Search Result:");

if (result != NULL) {

printf(" The symbol is present ");

} else {

printf(" The symbol is not present ");

}

break;

case 4:

exit(0);

}

} while (op < 4);

}