Problem:
Score : 100 points

Problem Statement

There are N items, numbered 1, 2, \ldots, N.
For each i (1 \leq i \leq N), Item i has a weight of w_i and a value of v_i.

Taro has decided to choose some of the N items and carry them home in a knapsack.
The capacity of the knapsack is W, which means that the sum of the weights of items taken must be at most W.

Find the maximum possible sum of the values of items that Taro takes home.

Constraints

All values in input are integers.

1 \leq N \leq 100

1 \leq W \leq 10^9

1 \leq w_i \leq W

1 \leq v_i \leq 10^3

Input

Input is given from Standard Input in the following format:

N W
w_1 v_1
w_2 v_2
:
w_N v_N

Output

Print the maximum possible sum of the values of items that Taro takes home.

Sample Input 1

3 8
3 30
4 50
5 60

Sample Output 1

90

Items 1 and 3 should be taken.
Then, the sum of the weights is 3 + 5 = 8, and the sum of the values is 30 + 60 = 90.

Sample Input 2

1 1000000000
1000000000 10

Sample Output 2

10

Sample Input 3

6 15
6 5
5 6
6 4
6 6
3 5
7 2

Sample Output 3

17

Items 2, 4 and 5 should be taken.
Then, the sum of the weights is 5 + 6 + 3 = 14, and the sum of the values is 6 + 6 + 5 = 17.

Solution in PyPy3 (2.4.0) (judge verdict: Accepted)

# atcoderのテスト用
# ./iunput/input.txt に入力を書き込む
n, W = map(int, input().split())
wv = [list(map(int, input().split())) for _ in range(n)]
w = [wv[i][0] for i in range(n)]
v = [wv[i][1] for i in range(n)]
inf = float('inf')
V = max(v)
vmax = 10**5+1
# dp[i][sum_v] 
# := i-1番目までの品物で価値がsum_vを超えないように選んだときの重さの総和の最小値
# 価値の合計はどれくらい大きくなるかわからないので十分に用意しとく
dp = [[inf for _ in range(vmax)] for _ in range(n+1)]
# 初期条件
dp[0][0] = 0
for i in range(n):
    for sum_v in range(vmax):
        # i番目の品物を選べるとき
        if sum_v - v[i] >= 0:
            dp[i+1][sum_v] = min(dp[i+1][sum_v], dp[i][sum_v - v[i]] + w[i])
        # i番目の品物を選ばないとき
        dp[i+1][sum_v] = min(dp[i+1][sum_v], dp[i][sum_v])


# 最適解を探す
ans = 0
for sum_v in range(vmax):
    if dp[n][sum_v] <= W:
        ans = sum_v
print(ans)