关于C结构体的一些代码补充

#include <stdio.h>
#include <stdlib.h>

typedef struct two_string
{
    char * first;
    char * second;
}ts;
void getmem(ts * t, unsigned first_n, unsigned second_n)
{
    t->first = (char *)malloc(sizeof(char) * first_n + 1);
    t->second = (char *)malloc(sizeof(char)* second_n +1);
}

void free_ts(ts * t)
{
    free(t->first);
    free(t->second);
}	
int main()
{
    ts pair_string;
    getmem(&pair_string,10,10);
    scanf("%s%s",pair_string.first, pair_string.second);
    printf("%s\n%s\n",pair_string.first, pair_string.second);
    free_ts(&pair_string);
    pair_string = (ts){"hello","world"};
    puts(pair_string.first);
    puts(pair_string.second);
    return 0;
}