stack_impl1.c

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

struct Stack {
    uint32_t used;
    int *array;
};

void destruct(struct Stack s)
{
    free(s.array);
}

void print_stack(const struct Stack s)
{
    uint32_t i = s.used;
    printf("stack length : %u\n",s.used);
    printf("Top :");
    for(; i != 0; --i) {
        printf(" %u ",s.array[i-1]);
    }
    puts("");
}

void DERUARU(struct Stack *s)
{
    s->used = 0;
    s->array = NULL;
}

void move(int *dst,struct Stack * const s)
{
    memcpy(dst,s->array,sizeof(int) * s->used);
    free(s->array);
    s->array = NULL;
}

void push(struct Stack * const s,int v)
{
    int *tmp = malloc(sizeof(int) * (s->used + 1));
    if(tmp == NULL)
        return;

    move(tmp,s);

    tmp[s->used] = v;
    ++s->used;
    s->array = tmp;

    return;
}

int top(struct Stack s)
{
    if(s.used == 0)
    {
        abort(); /* グワーッ!! */
    }
    else
        return s.array[s.used - 1];
}

void pop(struct Stack * const s)
{
    if(s->used == 0)
    {
        return;
    }
    else
    {
        int *tmp;
        tmp = malloc(sizeof(int) * (s->used - 1));
        if(tmp == NULL)
            return;

        --s->used;
        move(tmp,s);
        s->array = tmp;
        
        return;
    }
}

void pushloop(int i,struct Stack * const s)
{
    int nouse[40000];

    push(s,i);
    print_stack(*s);
    pushloop(i+1,s);
}

int main()
{
    struct Stack s;DERUARU(&s);

    print_stack(s);

    push(&s,1);
    print_stack(s);

    pop(&s);
    print_stack(s);

    push(&s,2);
    print_stack(s);

    destruct(s);

    return 0;
}