Problem:
Score : 200 points

Problem Statement

You are given two integers K and S.

Three variable X, Y and Z takes integer values satisfying 0≤X,Y,Z≤K.

How many different assignments of values to X, Y and Z are there such that X + Y + Z = S?

Constraints

2≤K≤2500

0≤S≤3K

K and S are integers.

Input

The input is given from Standard Input in the following format:

K S

Output

Print the number of the triples of X, Y and Z that satisfy the condition.

Sample Input 1

2 2

Sample Output 1

6

There are six triples of X, Y and Z that satisfy the condition:

X = 0, Y = 0, Z = 2

X = 0, Y = 2, Z = 0

X = 2, Y = 0, Z = 0

X = 0, Y = 1, Z = 1

X = 1, Y = 0, Z = 1

X = 1, Y = 1, Z = 0

Sample Input 2

5 15

Sample Output 2

1

The maximum value of X + Y + Z is 15, achieved by one triple of X, Y and Z.

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>
#include<stdlib.h>
int main()
{
    int k,s,x,y,z,n=0;
    scanf("%d%d",&k,&s);
    for(x=0;x<=s;x++)
    for(y=0;y<=s;y++)
    {
        z=s-x-y;
            if(x+y+z==s&&z>=0&&3*k>s)
            {
                n++;
                printf("x=%d,y=%d,z=%d\n",x,y,z);
            }
            if(3*k==s)
                {
                printf("1");
                exit(0);
                 }
    }
    printf("%d\n",n);
    return 0;
}