C - Simple Library Search from File

Search the Library by Author or Title from File.

This example uses Structs and Different Functions to process the different types and parts of the search.

// This is a rough copy of the Program.

Sample Input File Format:

library.txt

n // Num Different Books  
Title_Name AuthorFirst AuthorLast QoH  
Title_Name AuthorFirst AuthorLast QoH  
Title_Name AuthorFirst AuthorLast QoH

library.txt

5  
Tom_the_baker Dorris Twain 3  
Intro_to_C_Programming Allan King 2  
Happy_go_Lucky Dorris Twain 5  
The_one_who_fled_the_farm Joe Green 1  
George_junior jose maffia 18

librarySearch.c

/*
Library Search Service  
Program Created by: Michael Maffia  
*/

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

#define MAX_LENGTH 40
#define MAX_BOOKS 100

//Book Structure
struct book {  
    char title[MAX_LENGTH];
    char authorfname[MAX_LENGTH];
    char authorlname[MAX_LENGTH];
    int numcopies;
} bk;

//Function takes index number, and book struct to print all books by author.
void getBooksByIndex(int j, struct book bks[], int numbooks) {  
    int i;
    //Scans the Array of Structs and compares the full names of the Author with set index.
    printf("Names of all Books by %s: \n", bks[j].authorfname);
    printf("----------------------\n");
    for (i = 0; i < numbooks; i++) {
        if (strcmp(bks[j].authorfname, bks[i].authorfname) == 0) {
            printf("%s \nTotal Copies: %d \n\n", bks[i].title, bks[i].numcopies);
        }
    }
    printf("---------------------- \n\n");
}

// Function searches Library by Author First and Last Name
void searchByAuthor(char search[], struct book bks[], int numbooks) {  
    int i;
    int found = 0;
    char name[MAX_LENGTH];
    for (i = 0; i < numbooks; i++) {
        //Compares combined author name with user search.
        if (strcmp(search, bks[i].authorfname) == 0) {
            found = 1;
            printf("Good News! Your author has a book is in stock..\n\n");
            getBooksByIndex(i, bks, numbooks);
            break;
        }
    }
    //If no book is found, print.
    if (found == 0) {
        printf("Sorry, couldn't find a book.\n\n");
    }
}

// Function that processes a search by Title
void searchByTitle(char search[], struct book bks[], int numbooks) {  
    int i;
    int found = 0;
    //Loop that scans the array of structs and compares each index to the user's search.
    for (i = 0; i < numbooks; i++) {
        if (strcmp(search, bks[i].title) == 0) {
            found = 1;
            printf("Good News! Your book has been found.\n");
            printf("There are %d copies of your book.\n\n", bks[i].numcopies);
            getBooksByIndex(i, bks, numbooks);
            break;
        }
    }
    // If no book is found, print.
    if (found == 0) {
        printf("Sorry, couldn't find a book.\n\n");
    }
}

// Function that takes a user search input, processes by type.
void userSearch(struct book bks[], int numbooks) {  
    char choice;
    char search[MAX_LENGTH];
    char lastName[MAX_LENGTH];
    //Print Statements
    printf("Please Enter a Choice: \n");
    printf("---------------------- \n");
    printf("'a' to search by book title.\n");
    printf("'b' to search by author.\n");
    //Scan user choice to search
    scanf(" %c", &choice);
    //Search by Book Title
    if (choice == 'a' || choice == 'A') {
        printf("Enter the title of the book you want to search for? (Case Sensitive) \n");
        printf("Instead of a Space you must use '_' to separate words \n");
        scanf("%s", search);
        printf("\n");
        searchByTitle(search, bks, numbooks);
    }
    //Search by Author
    if (choice == 'b' || choice == 'B') {
        printf("All Entries are Case Sensitive!\n");
        printf("Enter the FIRST name of the Author you'd like to search for: \n");
        scanf("%s", search);
        printf("Enter the LAST name of the Author you'd like to search for: \n");
        scanf("%s", lastName);
        printf("\n");
        strcat(search, " ");
        strcat(search, lastName);
        searchByAuthor(search, bks, numbooks);
    }


}

// Main function. Populates an array of structs from text file. Executes program.
int main() {  
    // Opens the input File.
    FILE *input = fopen("library.txt", "r");
    //Default Start Choice
    char choice = 'y';
    //Declared Vars used in loop
    int numBookNames, i;
    //Scan for Number of Book Names
    fscanf(input, "%d", &numBookNames);
    // Declares an Array of book structs.
    struct book bks[numBookNames];
    // Loop scans each line for Book Title, Author First and Last name, and Number.
    for (i = 0; i < numBookNames; i++) {
        fscanf(input, " %s %s %s %d", &bks[i].title, &bks[i].authorfname, &bks[i].authorlname, &bks[i].numcopies);
        //String function to combine author first and last names after scanning from input.
        strcat(bks[i].authorfname, " ");
        strcat(bks[i].authorfname, bks[i].authorlname);
    }
    // Do-while Loop that runs each time the program is run, asks user if they want to continue
    do {
        userSearch(bks, numBookNames);
        printf("Would you like to continue using the Library? \nEnter 'Y' or 'y' to Continue. \n");
        scanf("  %c", &choice);

    } while (choice == 'y');
    //End of Program Message.
    printf("Goodbye.\n");
    //Closes the input File
    fclose(input);
    return 0;
}