c语言回文字判断

递归实现回文字判断

#include <stdio.h>
#include<string.h>
#include<stdlib.h>
#include <unistd.h>
/*****tonytrek*****2021.5.7*****/
/*****回文字判断*****/
int back_foward(int,int,char*,int);
int main()
{
    char* str=malloc(10);
    scanf("%s",str);
    printf("string is %s\n",str);
    sleep(2);
    int front=0;
    int back=strlen(str)-1;
    back_foward(front,back,str,strlen(str));
    return 0;
}
int back_foward(int front,int back,char* str,int rest)
{
    printf("start\n");
    if(rest==0||rest==1)
    {
        printf("yes!\n");
        return 1;
    }
    else
    {
        if(str[front]==str[back])
        {
            front=front++;
            back=back--;
            rest=rest-2;
            back_foward(front,back,str,rest);  //a Recursion
        }
        else
        {
            printf("no...\n");
            return 0;
        }
    }
}