c - 动态数组的问题

Question

这是一个非常愚蠢的问题，对此感到抱歉，但我白白浪费了很多时间:(。我知道动态数组有问题，但我看不出它不起作用的原因。

#include <stdio.h>
#include "Header.h"
#include <stdlib.h>
#include <iostream>


typedef struct Stack{
    T* arr;
    int num;
    int size;
}Stack;

typedef struct Iterator {
    Stack* stack;
}Iterator;

void initStackBitch(Stack* S) {
    S->size = 25;
    S->arr = (T*)(S->size * sizeof(*(S->arr)));
    S->num = 0;
}

void ReinitStack(Stack* S) {
    S->size = S->size * 2;
    S->arr = (T*)realloc(S->arr, S->size * sizeof(*(S->arr)));
}

void push(Stack* S, T Element) {
    if (IsStackFull(S)) {
        ReinitStack(S);
        cout << "Stack is remade";
    }
    else {
        S->arr[S->num] = Element;
        S->num++;
    }
}

T pop(Stack* S) {
    if (IsStackEmpty(S)) {
        printf("Stack is Empty");
        exit(2);
    }
    else {
        S->num--;
        return S->arr[S->num + 1];
    }
}

int IsStackFull(Stack* S) {
    if (S->num == S->size) {
        return 1;
    }
    else return 0;
}

int IsStackEmpty(Stack* S) {
    if (S->num == 0) {
        return 1;
    }
    else return 0;
}

Iterator* CreateIterator(Stack* S) {
    Iterator* iterator = (Iterator*)malloc(sizeof(Iterator));
    iterator->stack = S;
    return iterator;
}

bool HaveNext(Iterator* iterator) {
    return iterator->stack->num != iterator->stack->size;
}

void GoNext(Iterator* iterator) {
    if (HaveNext(iterator)) {
        iterator->stack->arr = iterator->stack->arr + 1;
    }
    return;
}

void* GetValue(Iterator* iterator) {
    if (HaveNext(iterator)) {
        return iterator->stack->arr;
    }
    else exit(-1);
}

void PrintStack(Stack* stack) {
    for (Iterator* iterator = CreateIterator(stack); HaveNext(iterator); GoNext(iterator)) {
        cout << GetValue(iterator) << endl;
    }
}

int main() {
    Stack S;
    initStackBitch(&S);
    push(&S, 1);
    push(&S, 2);
    push(&S, 3);
    pop(&S);
    PrintStack(&S);
    _fgetchar();
}

我知道错误在于推送

Answer 1

您必须在初始化时为arr分配内存。初始化后，Push 会尝试插入未分配(未定义)的内存，从而导致崩溃。所以错误不在push中:

void initStackBitch(Stack* S) {
    S->size = 25;
    S->arr = (T*)malloc(S->size * sizeof(*(S->arr)));
    S->num = 0;
}