Swapping two strings with Temporary Variable in C

#include<stdio.h>
#include<string.h>
#include<malloc.h>
#include<conio.h>
 
main()
{
   char first[50], second[50], *temp;
 
   printf("Enter string1 ");
   gets(first);
 
   printf("Enter string2 ");
   gets(second);
 
   printf("\nInitial status\n");
   printf("First string: %s\n",first);
   printf("Second string: %s\n\n",second);   
   
   temp = (char*)malloc(100); 
 
   strcpy(temp,first);
   strcpy(first,second);
   strcpy(second,temp);
 
   printf("After Swapping\n");
   printf("First string: %s\n",first);
   printf("Second string: %s\n",second);
 
   getch();
   return 0;
}