Using of string with sample example

#include<stdio.h>
#include<string.h>

int main (){
   char str[6] ={'h','e','l','l','o','\0'};
    printf("%s",str);
   
    //using strlen
    // strlen = string length
    printf("\nlength of string is %lu", strlen(str));
    //using strcpy
    /*strcpy (s1 ,s2)= copy secound string in frist string*/
   char str2[6];
    strcpy(str2,str);
    printf("\n string1 copied in  str2 = %s",str2);
   
    /* using of strncpy
    strncpy(s1,s2,length of string to be copied) = copies characters of a string s2 to     
    another string s1 up to  a speciafied length n */
    char str3[10];
    strncpy(str3,str,4);
    printf("\n after strncpy str3 is %s ",str3);
   
    return 0;
}