Question

Consider the data file “assignment-07-input.csv.

The data contains of 4 different things separated by comma – origin airport code (3 characters),

destination airport code (3 characters), airline code (2 characters), passenger count (integer).

There is no header row, so you do not have to deal with it. Write code to do the following:

• The program will take 3 extra command line arguments & use a makefile to run.

o Input file name

o Output file name

o Airline code

• Once run, the program should calculate the count the number of passengers for the

input airline code and write the count to the output file “assignment-07-output.txt”.

Your program should validate the command line arguments before continuing with the

main program execution.

• Read and parse the CSV file and store the data in a structure “RouteRecord”. Each

RouteRecord will have the following data members

o origin airport code (3 characters - SAT)

o destination airport code (3 characters - SAT)

o airline code (2 characters - AA)

o passenger count (integer)

• Create 3 separate files – routerecords.h, routerecords.c & a7.c

• Create different functions that are needed to read data from the file. Make sure to have

proper prototypes, header guards, header includes, etc.

o You must dynamically create an array of RouteRecords.

o The file will not contain the number of RouteRecords, you should read the file

once to know the value of N and then populate the array.

• Create function(s) which goes through the data array and calculates the number of

passengers for the input airline code. Write the number to the output file.

• You need to create a MAKEFILE.

• An example to run the program using the makefile would be

 make

 ./a7 assignment-07-input.csv assignment-07-output.csv AA

***csv file**

Part of Data Set

JFK	LHR	BA	87133
JFK	LHR	VS	61962
JFK	CDG	AF	61178
LGA	YYZ	AC	60792
SFO	TPE	BR	57801
MIA	LHR	BA	56095
JFK	STI	B6	55885
SFO	HKG	CX	55012
JFK	DXB	EK	54746
LAX	TPE	BR	54741
FLL	YUL	RV	54217
LAX	ICN	OZ	54103
LAX	HKG	CX	52285
DFW	CUN	AA	51561
JFK	SDQ	B6	51402
DFW	LHR	AA	49292
ATL	CUN	DL	49223
MIA	PTY	CM	48212
GUM	NRT	UA	46674
LAX	PEK	CA	46434
MIA	CUN	AA	45570
LAX	ICN	KE	45301
JFK	HKG	CX	45191
LAX	LHR	BA	45053
LAX	YYZ	AC	43925
LAX	MEX	AM	42424
MIA	HAV	AA	42310
MIA	BOG	AV	42134
JFK	ICN	KE	42050
EWR	LHR	UA	42022
MIA	GRU	JJ	41789
FLL	YYZ	RV	41383
ATL	YYZ	DL	41283
LAX	MNL	PR	40737
HNL	NRT	JL	40108
MCO	PTY	CM	39171

Answer 1

First of all the function prototypes foes in the file routerecords.h, so that any other program can use it's function

##ifndef ROUTERECORD_H
#define ROUTERECORD_H

typedef struct RouteRecord RouteRecord;

int countRows(char* input_file_path);

struct RouteRecord* readInputFile(char* input_file_path, int N);

int findAirlinePassengerCount(struct RouteRecord* data, char* given_code, int N);

void writeResult(char* output_file_path, int result);
#endif

Then here goes the definition of the functions declared in the header file, written in routerecords.c

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

typedef struct RouteRecord{
        char origin[10];
        char destination[10];
        char airline_code[10];
        int passenger_count;
} RouteRecord;

int countRows(char* input_file_path) {
        FILE *file = fopen(input_file_path, "r");
        char buf[16];
        if(!file) {
                printf("can't open the file\n");
                return -1;
        }
        int count = 0;
        while(fgets(buf, 1024, file)) count++;
        fclose(file);
    return count;
}

struct RouteRecord* readInputFile(char* input_file_path, int N) {
        FILE *file = fopen(input_file_path, "r");
    char buf[16];
    char *token; 
    if(!file) {
        printf("can't open the file\n");
        return NULL;
    }
    struct RouteRecord *array;
    array = malloc(N * sizeof(struct RouteRecord));
    int i = 0;
    while(fgets(buf, 1024, file)) {
        buf[16] = '\0';
        token = strtok(buf, ",");
        strcpy((array + i)->origin,token);
        token = strtok(NULL, ",");
        strcpy((array + i)->destination, token);
        token = strtok(NULL, ",");
        strcpy((array + i)->airline_code, token);
        token = strtok(NULL, ",");
        int passenger_count;
        sscanf(token, "%d", &(array + i)->passenger_count);
        token = NULL;
        i++;
    }
    fclose(file);
    return array;
}

int findAirlinePassengerCount(struct RouteRecord* data, char* given_code, int N){
    int count = 0;
    for(int i=0; i<N; i++)
        if(!strcmp(data[i].airline_code, given_code)) count += data[i].passenger_count;
    return count;
}

void writeResult(char* output_file_path, int result){
    FILE *fptr;
    fptr = fopen(output_file_path, "w");
    if (fptr == NULL) {
        printf("Can't create/open the file");
        exit(1);
    }
    fprintf(fptr, "%d", result);
    fclose(fptr);
    return;
}

and then finally the main program which uses the functionality that is defined above, written in file a7.c as follows,

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "routerecord.h"

int main(int argc, char* argv[]) {
    if(argc < 4) {
        printf("Three argument required < inpit file name, output file name, Airline codes >\n");
        return 1;
    }
    int N = countRows(argv[1]);
    struct RouteRecord* data = readInputFile(argv[1], N);
    int result = findAirlinePassengerCount(data, argv[3], N);
    writeResult(argv[2], result);
    return 0;
}

finally a make file for the above program,

assignment-07-output.txt : routerecord.o
    ./routerecord.o temp_in.csv "assignment-07-output.txt" VS
routerecord.o : a7.c routerecord.c routerecord.h
    gcc a7.c routerecord.c -o routerecord.o

The functions are written in the header file routerecord.h shown above which has it's function definitions in file routerecord.c which then used through the file a7.c. the read function reads the csv and store each row that is a record and save it to the dynamically allocated array. The airline code can be searched through that array and there we can get the total number of passangers in the airline with the specific airline code/