Output of character pointer to string in C language

The output of a string using a pointer of character type `

/* The use of pointers to achieve the assignment of strings */
#include<stdio.h>
char b[20];//global variable,
int main()
{
    

    char a[]="xin nian kuai le";
    void copy_char(char * p);
    copy_char(a);
    return 0;


}
/* Take character pointer type as parameter */
void copy_char(char * p)
{
    

    int i;
    for(i=0;*(p+i)!='\0';i++)//to judge if the character is '\0'
      *(b+i)=*(p+i);
      printf("after copied,this string is:\n");
      for(i=0;*(b+i)!='\0';i++)
            printf("%c",b[i]);

}

Output results ：after copied,this string is:
xin nian kuai le
Process returned 0 (0x0) execution time : 0.120 s
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