C語言--求字符串長度的三種解法

C語言--求字符串長度的三種解法

#include<stdio.h>
#include<assert.h>
int my_strlen( char* str)
{
    int count=0;
    while (*str)
    {
        count++;
        str++;
    }
    return count;
}
int main(void)
{
    char *arr = "abcef";
    int ret = my_strlen(arr);
    printf("%d\n", ret);
}

#include<stdio.h>
#include<assert.h>
int  my_strlen(const char*str)
{
    assert(srt);
    const char* ret = str;
    while (*ret++)
    {
        ;
    }
    return(ret - str-1);
}
     
int main(void)
{

    char *arr = "abcdef";
     printf("%d\n",my_strlen(arr));   
}

#include<stdio.h>
#include<assert.h>
int my_strlen(char* srt)
{
    assert(srt);
    if (*srt == '\0')
    {
        return 0;
    }
    else
    {    
        srt++;
        return (1 + my_strlen(srt));
         
    }
}
int main(void)
{
    char *arr = "abcdef";
    printf("%d\n", my_strlen(arr));
}