Cで線型Listを作ります

list.cpp

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct __physcheck
{
    char name[20];
    int height;
    double vision;
    struct __physcheck *next;
} PhysCheck;

// headとtailは[head,tail]の閉区間
PhysCheck *head = NULL;
PhysCheck *tail = NULL;

void add(char *name, int height, double vision)
{
    PhysCheck *x = malloc(1 * sizeof(PhysCheck));
    strcpy(x->name, name);
    x->height = height;
    x->vision = vision;
    x->next = NULL;
    if (head == NULL)
    {
        x->next = NULL;
        head = x;
        tail = head;
    }
    else
    {
        tail->next = x;
        tail = tail->next;
    }
}

PhysCheck *find(char *name)
{
    PhysCheck *crrPtr = head;
    PhysCheck *befPtr = NULL;
    while (crrPtr != NULL)
    {
        if (!strcmp(crrPtr->name, name))
        {
            return befPtr;
        }
        befPtr = crrPtr;
        crrPtr = crrPtr->next;
    }
    return NULL;
}

void delete (char *name)
{
    PhysCheck *befPtr = find(name);
    if (befPtr == NULL)
    {
        // 先頭
        PhysCheck *nextPtr = head->next;
        free(head);
        head = nextPtr;
    }
    else if (befPtr->next->next == NULL)
    {
        // 末尾
        free(befPtr->next);
        befPtr->next = NULL;
    }
    else
    {
        // 中間
        PhysCheck *nextPtr = befPtr->next->next;
        free(befPtr->next);
        befPtr->next = nextPtr;
    }
}

void print()
{
    PhysCheck *crrPtr = head;
    while (crrPtr != NULL)
    {
        printf("%s, %d, %f\n", crrPtr->name,
               crrPtr->height, crrPtr->vision);
        crrPtr = crrPtr->next;
    }
}

int main(void)
{

    add("AKASAKA Tadao", 162, 0.3);
    add("KATOH Tomiaki", 173, 0.7);
    add("NAGAHAMA Masaki", 168, 0.4);
    add("HAMADA Tetsuaki", 174, 1.2);

    print();
    printf("\n");

    delete ("NAGAHAMA Masaki"); // 中間
    print();
    printf("\n");

    delete ("HAMADA Tetsuaki"); // 末尾
    print();
    printf("\n");

    delete ("AKASAKA Tadao"); // 先頭
    print();
    printf("\n");

    return 0;
}