/*此程序的目的是输入一个字符串，判断是否是回文（比如abba,dijid就是回文）*/

#include<stdio.h>
#include<string.h>
int i=0;
char a[256]={0};

void first();
int pdhw(char ax[]);

void main()
{
   
    first();
        if(pdhw(a))
            printf("It is not a huiwen.");
        else
            printf("It is a huiwen.");
        getchar();
}

void first()
{
    int pass=1,oh;
   
    while(pass)
    {
        printf("Please input a word.\n");
        printf("The word:");
        while(a[i]!='\n')
        {
            if(i!=0)
                i++;                //这里不知道怎么的i不能增加
        scanf("%c",&a[i]);
        }
            if(i<=1)
            {
                printf("It is not allowed!\n");
                    printf("Please input again.\n");
            }
            else
                pass=0;  
    }
}

int pdhw(char ax[])
{
    int x;
    for(x=0,i--;(x<=i)||(i!=x);x++,i--)
        if(ax[x]!=ax[i])
        {
            return 0;
            break;
        }
        return 1;

}

还是帮我看看我的程序哪错了吧