顺序表的就地逆置

#include <stdio.h>

/*
题目：数据结构题集18页2.21
试写一个算法，实现顺序表的就地逆置，即利用原表的存储空间将线性表(a1,a2,...,an)逆置为(an,...,a2,a1)
*/

#define maxlen 50
#define DATATYPE int

typedef struct{
    DATATYPE arr[maxlen];
    int length;
}Seqlist;

void print_SQ(Seqlist list)
{
    for(int i=0;i<list.length;i++){
        printf("%d ",list.arr[i]);
    }
    printf("\n");
}

int main(void)
{
    Seqlist list = {{1,2,3,4,5},5};

    int tmp;
    for(int i=0,j=list.length-1;i<j;i++,j--){
        //list.arr[i]与list.arr[j]进行交换
        tmp = list.arr[i];
        list.arr[i] = list.arr[j];
        list.arr[j] = tmp;
    }

    print_SQ(list);
}