각종 문자열 반전 방법(이 또는 교환법, 귀속 방법, 이분 사상)

#include 
#include 
#include 
//a=a+b;b=a-b;a=a-b
char* reverse1(char* str)//  1
{
    int len=strlen(str);
    char* start=str;
    char* p=str+len-1;
    while(str
str=*str+*p;
        *p=*str-*p;
        *str=*str-*p;
        str++;
        p--;
    }
    return start;
}
//a=a^b;b=a^b;a=a^b    a!=b
char* reverse2(char* str)//  2
{
    int len=strlen(str);
    char* start=str;
    char* p=str+len-1;
    while(str
str=*str^*p;
        *p=*str^*p;
        *str=*str^*p;
        str++;
        p--;
    }
    return start;
}
//      
//  1                   
char* reverse3(char* str)//
{
    if(strlen(str)<2)
    {
        return str;
    }
    reverse3(str+1);
    int i;
    char *p=str;
    char first=*str;
    for(i=0;istr)-1;i++)
    {
        *p=*(p+1);
        p=p++;
    }
    *p=first;
    return str;
}
//             
char* reverse4(char* str,int left,int right)
{
    if(left>=right)
    {
        return str;
    }
    int temp=str[left];
    str[left]=str[right];
    str[right]=temp;
    reverse4(str,left+1,right-1);
    return str;
}
//           ，       2  1    ，    
char* reverse5(char str[],int left,int right)
{

    if(right-left==2||right-left==1)
    {
         int temp=str[left];
            str[left]=str[right];
            str[right]=temp;
            return str;
    }
    if(left>=right)
    {
        return str;
    }

    if((right-left)%2==0&&(right-left)>2)//    
    {
        int i,k;
        int mid=(right+left)/2;
        reverse5(str,left,mid-1);
        reverse5(str,mid+1,right);
        for(i=left,k=mid+1;ichar temp=str[i];
            str[i]=str[k];
            str[k]=temp;
        }
    }
    if((right-left)%2==1&&(right-left)>1)//    
    {
        int i,k;
        int mid=(right+left)/2;
        reverse5(str,left,mid);
        reverse5(str,mid+1,right);
        for(i=left,k=mid+1;i1,k<=right;i++,k++)
        {
            char temp=str[i];
            str[i]=str[k];
            str[k]=temp;
        }


    }
    return str;
}
int main()
{
    char c[100];
    scanf("%s",c);
    reverse5(c,0,strlen(c)-1);
    printf("%s",c);
    return 0;
}