単連結リストの整列 #100 二教科の成績の保持体の実装

インタフェイスを実装する。

school_record.c

#include <stdlib.h>
#include <string.h>
#include "school_record.h"

struct tag_school_record {
    char *name;
    const grade_t *maths;
    const grade_t *physics;
};

typedef enum {
    EGRADE_A = 5, EGRADE_B = 4, EGRADE_C = 3
} egrade_t;

struct tag_grade {
    egrade_t grade;
};

static grade_t grades[] = {{EGRADE_A}, {EGRADE_B}, {EGRADE_C}};
const grade_t * const GRADE_A = &grades[0];
const grade_t * const GRADE_B = &grades[1];
const grade_t * const GRADE_C = &grades[2];

school_record_t *school_record_new(const char *name, const grade_t *maths, const grade_t *physics)
{
    school_record_t *p = NULL;
    if (name != NULL) {
        p = malloc(sizeof(school_record_t));
        if (p != NULL) {
            p->name = malloc(strlen(name) + 1);
            if (p->name != NULL) {
                strcpy(p->name, name);
                p->maths = maths;
                p->physics = physics;
            } else {
                free(p);
            }
        }
    }
    return p;
}

void school_record_dispose(school_record_t *rec)
{
    free(rec->name);
    free(rec);
}

const char *school_record_get_name(const school_record_t *rec)
{
    return rec->name;
}

const grade_t *school_record_get_maths(const school_record_t *rec)
{
    return rec->maths;
}

const grade_t *school_record_get_physics(const school_record_t *rec)
{
    return rec->physics;
}

int grade_compare(const grade_t *g1, const grade_t *g2)
{
    if (g1->grade > g2->grade) return 1;
    else if (g1->grade == g2->grade) return 0;
    else return -1;
}

特に工夫も何もなく。