回文是指正读和反读均相同的字符序列，如”abba”和”abdba”均是回文，但”good”不是回文，试用c语言写一算法利用栈判定给定的字符序列是否为回文。（提示：将一半字符入栈）

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

#define MAX_SIZE 100

typedef struct {
    char data[MAX_SIZE];
    int top;
} Stack;

void initStack(Stack *s) {
    s->top = -1;
}

bool isStackEmpty(Stack *s) {
    return s->top == -1;
}

bool isStackFull(Stack *s) {
    return s->top == MAX_SIZE - 1;
}

void push(Stack *s, char c) {
    if (isStackFull(s)) {
        printf("Stack is full.\n");
        exit(1);
    }
    s->top++;
    s->data[s->top] = c;
}

char pop(Stack *s) {
    if (isStackEmpty(s)) {
        printf("Stack is empty.\n");
        exit(1);
    }
    char c = s->data[s->top];
    s->top--;
    return c;
}

bool isPalindrome(char *str) {
    int len = strlen(str);
    Stack s;
    initStack(&s);
    int i;
    for (i = 0; i < len / 2; i++) {
        push(&s, str[i]);
    }
    if (len % 2 == 1) {
        i++;
    }
    while (str[i] != '\0') {
        if (pop(&s) != str[i]) {
            return false;
        }
        i++;
    }
    return true;
}

int main() {
    char str[MAX_SIZE];
    printf("Input a string: ");
    scanf("%s", str);
    if (isPalindrome(str)) {
        printf("%s is palindrome.\n", str);
    } else {
        printf("%s is not palindrome.\n", str);
    }
    return 0;
}