C语言 分析逆序字符串与字符串的逆序输出有什么区别

#include<stdio.h>
#include<string.h>
int main()
{
 
char arr[]="1234567";
int i=0;
int sz=strlen(arr);
for(i=sz-1;i>=0;i--)
  {
  printf("%c",arr[i]);
  }
  return 0;
}

#include<stdio.h>
#include<string.h>
void reverse(char* left, char *right)
{
	while (left < right)
	{
		char temp = *left;
		*left = *right;
		*right = temp;
		left++;
		right--;
	}
 
}
int main()
{
	char arr[] = "1234567";
	int sz = strlen(arr);
	int i = 0;
	reverse(arr, arr+sz-1);
	for (i = 0; i < sz; i++)
	{
		printf("%c", arr[i]);
	}
	return 0;
}

void reverse(char* left, char* right)
{
	while (left < right)
	{
		char temp = *left;
	    *left = *right;        
		*right = temp;
		left++;
		right--;
	}
}
int main()
{
	char arr[100] = { 0 };
    //输入字符串
	gets(arr);     
	int sz = strlen(arr);
    //将字符串进行整体的倒置
	reverse(arr, arr + sz - 1);    
    //将部分字符串进行倒置
	char* start = arr;
	
	while (*start)
	{
		char* end = start;
		while (*end != ' ' && *end!='\0')
		{
			end++;
		}
		reverse(start, end - 1);
		if (*end == ' ')
		{
			start = end + 1;
		}
		else
		{
			start = end;
		}
	 	
	   }
	printf("%s", arr);
	return 0;
}