Problem:
Score : 200 points

Problem Statement

There are some animals in a garden. Each of them is a crane with two legs or a turtle with four legs.

Takahashi says: "there are X animals in total in the garden, and they have Y legs in total." Determine whether there is a combination of numbers of cranes and turtles in which this statement is correct.

Constraints

1 \leq X \leq 100

1 \leq Y \leq 100

All values in input are integers.

Input

Input is given from Standard Input in the following format:

X Y

Output

If there is a combination of numbers of cranes and turtles in which the statement is correct, print Yes; otherwise, print No.

Sample Input 1

3 8

Sample Output 1

Yes

The statement "there are 3 animals in total in the garden, and they have 8 legs in total" is correct if there are two cranes and one turtle. Thus, there is a combination of numbers of cranes and turtles in which the statement is correct.

Sample Input 2

2 100

Sample Output 2

No

There is no combination of numbers of cranes and turtles in which this statement is correct.

Sample Input 3

1 2

Sample Output 3

Yes

We also consider the case in which there are only cranes or only turtles.

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

#include <bits/stdc++.h>

#define rep(i,n) for(int i=0;i<(n);++i)
#define repA(i,a,n) for(int i=a;i<=(n);++i)
#define repD(i,a,n) for(int i=a;i>=(n);--i)

using namespace std;

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    //x = total # of animal1 2
    //y = total # of legs

    int x, y;
    int crane, turtle;
    cin >> x >> y;

    if(y%2 != 0){
    	cout << "No";
    	return 0;
    }else if(x == 1 && (y == 4 || y == 2)){
    	cout << "Yes";
    	return 0;
    }else{
    	turtle = y/2-x;
    	crane = x - turtle;
    	crane <= 0 ? cout << "No" : cout << "Yes";
    }
}