Problem:
Score : 200 points

Problem Statement

Given are integers a,b,c and d.
If x and y are integers and a \leq x \leq b and c\leq y \leq d hold, what is the maximum possible value of x \times y?

Constraints

-10^9 \leq a \leq b \leq 10^9

-10^9 \leq c \leq d \leq 10^9

All values in input are integers.

Input

Input is given from Standard Input in the following format:

a b c d

Output

Print the answer.

Sample Input 1

1 2 1 1

Sample Output 1

2

If x = 1 and y = 1 then x \times y = 1.
If x = 2 and y = 1 then x \times y = 2.
Therefore, the answer is 2.

Sample Input 2

3 5 -4 -2

Sample Output 2

-6

The answer can be negative.

Sample Input 3

-1000000000 0 -1000000000 0

Sample Output 3

1000000000000000000

Solution in C (GCC 9.2.1) (judge verdict: Wrong Answer)

#include <stdio.h>
#include <math.h>




int main() {
    double a,b,c,d,w,x,y,z;
    scanf("%lf%lf%lf%lf", &a,&b,&c,&d);
    w = a*c;
    x = a*d;
    y = b*c;
    z = b*d;
    if (w>x && w>y && w> z)
    printf("%0.0lf", w);
    else if (x>w && x>y && x> z)
    printf("%0.0lf", x);
    else if (y>x && y>w && y> z)
    printf("%0.0lf",y);
    else if (z>x && z>y && z> w)
    printf("%0.0lf",z);










return 0 ;
}