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You have N items that you want to put them into a knapsack. Item i has value vi and weight wi.

You want to find a subset of items to put such that:

• The total value of the items is as large as possible.
• The items have combined weight at most W, that is capacity of the knapsack.

Find the maximum total value of items in the knapsack.

Input

N Wv1 w1v2 w2:vN wN

The first line consists of the integers N and W. In the following lines, the value and weight of the i-th item are given.

Output

Print the maximum total values of the items in a line.

Constraints

• 1 ≤ N ≤ 100
• 1 ≤ vi ≤ 1000
• 1 ≤ wi ≤ 1000
• 1 ≤ W ≤ 10000

Sample Input 1

4 54 25 22 18 3

Sample Output 1

13

Sample Input 2

2 205 94 10

Sample Output 2

9

 递推关系：

dp[i][j]=max(dp[i-1][j],dp[i-1][j-b[i].w]+b[i].v);

注意要做好初始化。。。

代码如下：

#include 
   
    #include 
    
     #include 
     
      #include 
      
       using namespace std;const int maxn=105;const int maxw=10005;int n,w;struct bag{    int v;    int w;};bag b[maxn];int dp[maxn][maxw];int main(){    scanf("%d%d",&n,&w);    for (int i=1;i<=n;i++)        scanf("%d%d",&b[i].v,&b[i].w);    for (int i=0;i<=w;i++)        dp[0][i]=0;    for (int i=1;i<=n;i++)        dp[i][0]=0;    for (int i=1;i<=n;i++)    {        for (int j=1;j<=w;j++)        {            dp[i][j]=dp[i-1][j];            if(j
      
     
    
   

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