C-(函数)字符串逆序

#define _CRT_SECURE_NO_WARNINGS 1

#include<stdio.h>//字符串逆序
int my_strlen(char* str)
{
    int count = 0;
    while (*str != '\0')
    {
        count++;
        str++;
    }
    return count;
}
void reverse_string(char* str)
{
    int left = 0;
    int right = my_strlen(str)-1;

    while (left<right)
    {
        char tmp = str[left];
        str[left] = str[right];
        str[right] = tmp;
        left++;
        right--;
    }
}
int main()
{
    char arr[] = "abcdef";

    reverse_string(arr);
    printf("%s\n", arr);
    return 0;
}