Files
c-schedule-generator/main.c
T
2024-10-03 17:19:44 -07:00

484 lines
15 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <stdint.h>
#include <sys/stat.h>
#include <math.h>
// Import and define proper functions depending on OS
#ifdef _WIN32
#include <direct.h>
#define MKDIR(name) _mkdir(name)
#else
#include <unistd.h>
#define MKDIR(name) mkdir(name, 0777)
#endif
/*
Using define instead of constants prevents
"Variable modified error"
*/
// Important constants
#define MAX_PUPIL_NUM_LEN 8
#define MAX_COURSE_DES_LEN 50
#define MAX_COURSE_NO_LEN 21
#define MAX_COURSE_ID_LEN MAX_COURSE_NO_LEN + 4 // 4 includes the underscore and the 3 digit unique number to identify the course
#define TOTAL_BLOCKS 10 // the number of blocks between 2 semesters i.e 8 = 4 blocks per semester, 10 = 5 blocks per semester
#define MAX_REQUEST_ALTS 6
#define CLASSROOMS 40
#define MIN_REQ 18
#define CLASS_CAP 30
#define MAX_STUDENTS CLASS_CAP * CLASSROOMS
#define MAX_COURSES CLASSROOMS * TOTAL_BLOCKS
// 5 is the length of "FALSE" & 3 is the number of commas per line
#define MAX_CHAR MAX_PUPIL_NUM_LEN + MAX_COURSE_NO_LEN + MAX_COURSE_DES_LEN + 5 + 3
/*** DEFINE CSV READER FUNCTIONS & DATASTRUCTURES ***/
typedef struct {
uint32_t pupilNum;
char crsNo[MAX_COURSE_NO_LEN];
char description[MAX_COURSE_DES_LEN];
bool alternate;
} CSV_LINE;
// Dumbass me set this to size_t earlier, forgot that size_t is unsigned and I can't return -1 on failure
int count_lines(char data_dir[]) {
FILE *stream = fopen(data_dir, "r");
if (!stream) {
fputs("Failed to open CSV file\n", stderr);
return -1;
}
char buff[MAX_CHAR];
size_t counter = 1;
while (fgets(buff, sizeof(buff), stream) != NULL) {
if (strchr(buff, '\n') != NULL) counter++;
}
fclose(stream);
return counter;
}
CSV_LINE *csvReader(char data_dir[], size_t size) {
FILE *stream = fopen(data_dir, "r");
if (!stream) {
fputs("Failed to open CSV file\n", stderr);
return NULL;
}
CSV_LINE *lines = malloc(size * sizeof(CSV_LINE));
char buff[MAX_CHAR];
int i = 0;
// Read each line in CSV file
while (fgets(buff, sizeof(buff), stream)) {
CSV_LINE csv_line;
lines[i] = csv_line;
// Tokenize the line to extract data
char *token = strtok(buff, ",");
if (token)
lines[i].pupilNum = atoi(token); // convert string to uint32_t
token = strtok(NULL, ",");
if (token)
strncpy(lines[i].crsNo, token, MAX_COURSE_NO_LEN);
token = strtok(NULL, ",");
if (token)
strncpy(lines[i].description, token, MAX_COURSE_DES_LEN);
token = strtok(NULL, ",");
if (token) {
char alternate[5];
strncpy(alternate, token, 5);
alternate[strcspn(alternate, "\n")] = 0; // Remove newline
lines[i].alternate = !strcmp(alternate, "TRUE") ? true : false;
}
i++;
}
fclose(stream);
return lines;
}
/*** DEFINE STUDENT DATA STRUCTURES & COURSE DATA STRUCTURES***/
typedef struct {
char crsNo[MAX_COURSE_NO_LEN];
char description[MAX_COURSE_DES_LEN];
bool alternate;
} REQUEST;
typedef struct {
uint32_t pupilNum;
REQUEST *requests;
uint8_t requestsLen;
char **schedule;
uint8_t expectedClasses;
uint8_t classes;
REQUEST *remainingAlts;
uint8_t remainingAltsLen;
uint8_t grade;
} STUDENT;
typedef struct {
char crsNo[MAX_COURSE_NO_LEN];
uint16_t requests;
char description[MAX_COURSE_DES_LEN];
uint8_t credits;
uint32_t students[CLASS_CAP];
uint8_t numberOfStudents;
} COURSE;
/*** DEFINE GET FUNCTIONS FOR STUDENTS & COURSES FROM CSV ***/
bool intInArray(uint32_t val, uint32_t *arr, size_t size) {
for (size_t i = 0; i < size; i++)
if (arr[i] == val)
return true;
return false;
}
/*
TODO: find a way to make the arr paramter work with any size, i.e char **arr
However, when I call this array I can't seem to be able to pass the string array
I want without it throwing an error when using char **arr as the parameter
*/
bool strInArray(char *str, char arr[MAX_COURSES][MAX_COURSE_NO_LEN], size_t size) {
for (size_t i = 0; i < size; i++)
if (strcmp(arr[i], str) == 0)
return true;
return false;
}
typedef struct {
uint32_t uniquePupilNumbers[MAX_STUDENTS];
size_t numberOfStudents;
} UNIQUE_STUDENTS;
UNIQUE_STUDENTS getNumberOfStudents(CSV_LINE *lines, size_t lines_len) {
// Find the number of unique students and store each unique pupil Num
UNIQUE_STUDENTS students_info = {{0}, 0};
for (size_t i = 0; i < lines_len; i++) {
bool exists = intInArray(lines[i].pupilNum, students_info.uniquePupilNumbers, students_info.numberOfStudents);
if (!exists) {
students_info.uniquePupilNumbers[students_info.numberOfStudents] = lines[i].pupilNum;
students_info.numberOfStudents++;
}
}
return students_info;
}
STUDENT *getStudents(CSV_LINE *lines, size_t lines_len, int total_blocks, UNIQUE_STUDENTS students_info) {
// Calculate each students number of requests to allocate the requests array
uint8_t numRequests[MAX_STUDENTS] = {0};
for (size_t i = 0; i < lines_len; i++) {
for (size_t j = 0; j < students_info.numberOfStudents; j++) {
if (students_info.uniquePupilNumbers[j] == lines[i].pupilNum) {
numRequests[j]++;
break;
}
}
}
// Create our student array with the correct number of students
STUDENT *students = malloc(students_info.numberOfStudents * sizeof(STUDENT));
for (uint16_t i = 0; i < students_info.numberOfStudents; i++) {
STUDENT student;
student.pupilNum = students_info.uniquePupilNumbers[i];
student.expectedClasses = 0;
student.classes = 0;
student.grade = 0;
student.requestsLen = 0;
student.remainingAltsLen = 0;
REQUEST *requests = malloc(numRequests[i] * sizeof(REQUEST));
student.requests = requests;
char **schedule = malloc(TOTAL_BLOCKS * sizeof(int*));
student.schedule = schedule;
REQUEST *remainingAlts = malloc(MAX_REQUEST_ALTS * sizeof(REQUEST));
student.remainingAlts = remainingAlts;
students[i] = student;
}
// Read each request in lines and assign to correct student
for (size_t i = 0; i < lines_len; i++) {
for (uint16_t j = 0; j < students_info.numberOfStudents; j++) {
if (lines[i].pupilNum == students[j].pupilNum) {
REQUEST request;
strcpy(request.crsNo, lines[i].crsNo);
strcpy(request.description, lines[i].description);
request.alternate = lines[i].alternate;
students[j].requests[students[j].requestsLen] = request;
students[j].requestsLen++;
break;
}
}
}
return students;
}
typedef struct {
char uniqueCrsNos[MAX_COURSES][MAX_COURSE_NO_LEN];
uint16_t numberOfCourses;
} UNIQUE_COURSES;
UNIQUE_COURSES getNumberOfCourses(CSV_LINE *lines, size_t lines_len) {
// Find the number of unique courses and store each unique course no.
UNIQUE_COURSES unique_course_info = {{{"\0"}}, 0};
for (size_t i = 0; i < lines_len; i++) {
bool exists = strInArray(lines[i].crsNo, unique_course_info.uniqueCrsNos, unique_course_info.numberOfCourses);
if (!exists) {
strcpy(unique_course_info.uniqueCrsNos[unique_course_info.numberOfCourses], lines[i].crsNo);
unique_course_info.numberOfCourses++;
}
}
return unique_course_info;
}
COURSE *getCourses(CSV_LINE *lines, size_t lines_len, UNIQUE_COURSES unique_course_info) {
COURSE *courses = malloc(unique_course_info.numberOfCourses * sizeof(COURSE));
for (size_t i = 0; i < unique_course_info.numberOfCourses; i++) {
for (size_t j = 0; j < lines_len; j++) {
if (strcmp(lines[j].crsNo, unique_course_info.uniqueCrsNos[j]) == 0) {
COURSE course = {"\0", 0, "\0", 4, {0}, 0}; // Ensure array of pupil numbers is null till we populate it later with the correct size
strcpy(course.crsNo, lines[i].crsNo);
strcpy(course.description, lines[i].description);
courses[i] = course;
break;
}
}
}
return courses;
}
// Yeah the above functions are not optimal, doing the same loop over and over in different places but oh well, works for me
/*** DEFINE JSON FUNCTION HANDLERS ***/
int createDirectory(const char *dir_name) {
// check if directory already exists
struct stat statbuf;
if (stat(dir_name, &statbuf) == 0 && S_ISDIR(statbuf.st_mode))
return 0; // Directory exists
if (MKDIR(dir_name) == 0) {
return 1; // Directory created
} else {
fputs("Failed to create directory", stderr);
return -1;
}
}
int writeStudentsToJson(STUDENT *students, size_t numberOfStudents, char output_dir[]) {
FILE *stream = fopen(output_dir, "w");
if (!stream) {
fputs("Failed to open students output file", stderr);
return -1;
}
fprintf(stream, "[\n");
for (size_t i = 0; i < numberOfStudents; i++) {
fprintf(stream, " {\n");
fprintf(stream, " \"pupilNum\": %d,\n", students[i].pupilNum);
fprintf(stream, " \"requests\": [\n");
for (size_t j = 0; j < students[i].requestsLen; j++) {
fprintf(stream, " {\n");
fprintf(stream, " \"crsNo\": \"%s\",\n", students[i].requests[j].crsNo);
fprintf(stream, " \"description\": \"%s\",\n", students[i].requests[j].description);
fprintf(stream, " \"alternate\": %s\n", students[i].requests[j].alternate ? "true" : "false");
fprintf(stream, " }%s\n", j == students[i].requestsLen - 1 ? "" : ",");
}
fprintf(stream, " ],\n");
fprintf(stream, " \"requestsLen\": %d,\n", students[i].requestsLen);
if (students[i].classes > 0) {
fprintf(stream, " \"schedule\": [\n");
for (size_t j = 0; j < students[i].classes; j++) {
fprintf(stream, " \"%s\"%s\n", students[i].schedule[j], j == students[i].classes - 1 ? "" : ",");
}
fprintf(stream, " ],\n");
} else {
fprintf(stream, " \"schedule\": [],\n");
}
fprintf(stream, " \"expectedClasses\": %d,\n", students[i].expectedClasses);
fprintf(stream, " \"classes\": %d,\n", students[i].classes);
if (students[i].remainingAltsLen > 0) {
fprintf(stream, " \"remainingAlts\": [\n");
for (size_t j = 0; j < students[i].remainingAltsLen; j++) {
fprintf(stream, " {\n");
fprintf(stream, " \"crsNo\": \"%s\",\n", students[i].remainingAlts[j].crsNo);
fprintf(stream, " \"description\": \"%s\",\n", students[i].remainingAlts[j].description);
fprintf(stream, " \"alternate\": %s\n", students[i].remainingAlts[j].alternate ? "true" : "false");
fprintf(stream, " }%s\n", j == students[i].remainingAltsLen - 1 ? "" : ",");
}
fprintf(stream, " ],\n");
} else {\
fprintf(stream, " \"remainingAlts\": [],\n");
}
fprintf(stream, " \"grade\": %d\n", students[i].grade);
fprintf(stream, " }%s\n", i == numberOfStudents - 1 ? "" : ",");
}
fprintf(stream, "]");
fclose(stream);
return 0;
}
int writeCoursesToJson(COURSE *courses, size_t numberOfCourses, char output_dir[]) {
FILE *stream = fopen(output_dir, "w");
if (!stream) {
fputs("Failed to open courses output file", stderr);
return -1;
}
fprintf(stream, "[\n");
for (size_t i = 0; i < numberOfCourses; i++) {
fprintf(stream, " {\n");
fprintf(stream, " \"crsNo\": \"%s\",\n", courses[i].crsNo);
fprintf(stream, " \"requests\": %d,\n", courses[i].requests);
fprintf(stream, " \"description\": \"%s\",\n", courses[i].description);
fprintf(stream, " \"credits\": %d,\n", courses[i].credits);
if (courses[i].numberOfStudents > 0) {
fprintf(stream, " \"students\": [\n");
for (size_t j = 0; j < courses[i].numberOfStudents; j++) {
fprintf(stream, " \"%d\"%s\n", courses[i].students[j], j == courses[i].numberOfStudents - 1 ? "" : ",");
}
fprintf(stream, " ],\n");
} else {
fprintf(stream, " \"students\": [],\n");
}
fprintf(stream, " \"numberOfStudents\": %d\n", courses[i].numberOfStudents);
fprintf(stream, " }%s\n", i == numberOfCourses - 1 ? "" : ",");
}
fprintf(stream, "]");
fclose(stream);
return 0;
}
/*** ALGORITHM ***/
typedef struct {
// 0-9 block idx | CRS_NO_ID | pupilNums
uint16_t timetable[TOTAL_BLOCKS][MAX_COURSE_ID_LEN][CLASS_CAP];
bool success;
} TIMETABLE;
char FLEX[2][11] = {"XAT--12A-S", "XAT--12B-S"};
TIMETABLE generateTimetable(STUDENT *students, size_t size_students, COURSE *courses, size_t size_courses) {
TIMETABLE timetable = {{{{0}}}, 0};
uint8_t median = floor((MIN_REQ + CLASS_CAP) / 2);
uint8_t blocksPerSemester = TOTAL_BLOCKS / 2;
// Step 1 - Tally requests to check which courses are eligable to run
char activeCourses[MAX_COURSES][MAX_COURSE_NO_LEN] = {{"\0"}};
size_t activeCoursesIndexes[MAX_COURSES] = {0};
uint16_t activeCourseIndex = 0;
for (size_t i = 0; i < size_students; i++) {
for (size_t j = 0; j < students[i].requestsLen; j++) {
if (students[i].requests[j].alternate) continue;
if (strcmp(students[i].requests[j].crsNo, FLEX[0]) == 0) continue;
if (strcmp(students[i].requests[j].crsNo, FLEX[1]) == 0) continue;
for (size_t k = 0; k < size_courses; k++) {
if (strcmp(courses[k].crsNo, students[i].requests[j].crsNo) == 0) {
courses[k].requests++;
if (courses[k].requests >= MIN_REQ) {
if (activeCourseIndex == 0) {
strcpy(activeCourses[activeCourseIndex], courses[k].crsNo);
activeCoursesIndexes[activeCourseIndex] = k;
activeCourseIndex++;
} else {
bool exists = false;
for (size_t l = 0; l < activeCourseIndex; l++) {
if (strcmp(activeCourses[l], courses[k].crsNo) == 0) {
exists = true;
break;
}
}
if (!exists) {
strcpy(activeCourses[activeCourseIndex], courses[k].crsNo);
activeCoursesIndexes[activeCourseIndex] = k;
activeCourseIndex++;
}
}
}
break;
}
}
}
}
return timetable;
}
/*** MAIN ***/
int main(int argc, char **argv) {
/*
read csv data into array of structs that can
be processed into an array of student structs
and an array of course structs
*/
char data_dir[] = "sample_data/course_selection_data.csv";
int num_lines = count_lines(data_dir);
if (num_lines == -1) {
fputs("Failed to read number of lines in the givengiven CSV file!\n", stderr);
return -1;
}
CSV_LINE *lines = csvReader(data_dir, num_lines);
if (lines == NULL) return -1;
// Get number of students & number of courses
UNIQUE_STUDENTS students_info = getNumberOfStudents(lines, num_lines);
UNIQUE_COURSES courses_info = getNumberOfCourses(lines, num_lines);
// Create struct array of students & courses
STUDENT *students = getStudents(lines, num_lines, TOTAL_BLOCKS, students_info);
if (students == NULL) return -1;
COURSE *courses = getCourses(lines, num_lines, courses_info);
if (courses == NULL) return -1;
free(lines);
// Algorithm here
TIMETABLE timetable = generateTimetable(students, students_info.numberOfStudents, courses, courses_info.numberOfCourses);
// Write data to json for output
if (createDirectory("output") == -1) return -1;
if (writeStudentsToJson(students, students_info.numberOfStudents, "output/students.json") == -1) return -1;
if (writeCoursesToJson(courses, courses_info.numberOfCourses, "output/courses.json") == -1) return -1;
free(students);
free(courses);
return 0;
}