How can we store the return value of "strstr()" in an "int" variable in C Language ?

Question

As per the C language, the strstr function returns a "char*". So how is the following code running fine and printing "true" ?
[ I got this question in a challenge of Me Vs SoloLearn ]
Help me out guys !!!

CODE :

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

void main()
{
char * str1 = "Hello World";
char * str2 = "rl";

int a = strstr(str1,str2);

if(a!='\0')
printf("true");
else
printf("false");
}

Answer 1

you can't because the return value is not an int but a pointer to the first occurrence of str2, if str2 cannot be found the return value is NULL, so you can work your way around that by using if(strstr(str1, str2)!=NULL)

Answer 2

We can use char* , I run the above program , It shows no ERROR
Am ,I Write.....