Problem:
Score : 200 points

Problem Statement

Snuke has come to a store that sells boxes containing balls. The store sells the following three kinds of boxes:

Red boxes, each containing R red balls

Green boxes, each containing G green balls

Blue boxes, each containing B blue balls

Snuke wants to get a total of exactly N balls by buying r red boxes, g green boxes and b blue boxes.
How many triples of non-negative integers (r,g,b) achieve this?

Constraints

All values in input are integers.

1 \leq R,G,B,N \leq 3000

Input

Input is given from Standard Input in the following format:

R G B N

Output

Print the answer.

Sample Input 1

1 2 3 4

Sample Output 1

4

Four triples achieve the objective, as follows:

(4,0,0)

(2,1,0)

(1,0,1)

(0,2,0)

Sample Input 2

13 1 4 3000

Sample Output 2

87058

Solution in Ruby (2.3.3) (judge verdict: Time Limit Exceeded)

rgbn=gets.chomp.split.map{|a| a.to_i}
r_jogen=rgbn[3]/rgbn[0]
count=0
for i in 0..r_jogen do
  g_jogen=(rgbn[3]-rgbn[0]*i)/rgbn[1]
  for j in 0..g_jogen do
    b_jogen=(rgbn[3]-rgbn[0]*i-rgbn[1]*j)/rgbn[2]
    for k in 0..b_jogen do
      count+=1 if rgbn[3]==rgbn[0]*i+rgbn[1]*j+rgbn[2]*k
    end
  end
end

puts count