字符串函数的封装

#include "stdio.h"
#include "stdlib.h"




int mystrlen(char* dest)
{
    int length=0;
    while (*dest!='\0')
    {
        length++;
        dest++;
    }
    return length;

}

char *mystrcpy(char* dest ,char* source)
{
    char *destbak=dest;
    while (*source!='\0')
    {
        *dest++=*source++;
    }
    *dest='\0';
    return destbak;

}
char* mystrcat(char* dest,char* source)
{
    char *destbak=dest;
    while (*dest!='\0')
    {
        dest++;
    }
    while (*source!='\0')
    {
        *dest++=*source++;
    }
    *dest='\0';
    return destbak;

}
int mystrcmp(char *s , char *t )
{
while( *s && *t && *s == *t ) s++,t++;
return *s - *t;
}
void main()
{
    char str1[]={"nihao"};
    char str2[]={"nihao"};
    int length=mystrlen(str2);
    printf("str1Length=%d\n",length);

    //char *p=mystrcpy(str1,str2);
    //printf("%s\n",p);
//    char *pstrcat=mystrcat(str1,str2);
    //printf("%s\n",pstrcat);

    int N=mystrcmp(str1,str2);
    if (N==0)
    {
        printf("相等");
    }
    else
    {
        printf("不等");
    }


    getchar();

}