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 C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;
#define int  long long int
#define mod 1000000000000007
#define pb push_back
#define mp make_pair
#define bs binary_search
#define lb lower_bound
#define ub upper_bound
#define gcd __gcd
#define fastio ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define min3(a,b,c) min(a,min(b,c))
#define max3(a,b,c) max(a,max(b,c))
#define all(i) i.begin(),i.end()
#define rep(i,a,b) for(int i=a;i<b;i++)
#define set_bit __builtin_popcount //gives number of set_bits
#define ff first
#define ss second
#define cases(t) int t;cin>>t; rep(casn,1,t+1)
#define el cout<<"\n";
#define deci(n) int n; scanf("%lld",&n);
#define decs(n) string n; cin>>n;
#define sz(v) v.size()
#define repit(m) for(auto it=m.begin();it!=m.end();it++)
// #define find(m,i) (m.find(i)!=m.end())
// #define find(m,i) (m.find(i)==m.end())
#define cYES cout<<"YES\n";
#define cNO cout<<"NO\n";
#define ins insert
#define imax 1000000000000000000
#define imin -1000000000000000000
// #define NP 50000
//  cerr << "\nTime : " << (double)clock() / (double)CLOCKS_PER_SEC << "s\n";
 
//  IIITA
//SUNEET KUMAR -->  ਸੁਨੀਤ
 
// scanning numbers extremely fast/////////
void fs(int &number)
{
    bool negative = false;
    register int c;
    number = 0;
    c = getchar();
    if (c=='-')
    {
        negative = true;
        c = getchar();
    }
    for (; (c>47 && c<58); c=getchar())
        number = number *10 + c - 48;
    if (negative)
        number *= -1;
}
// ========================================
int power(int a,int x)
{
        a%=mod;
    int res=1;
    while(x>0)
    {
        if(x&1)
        res=res*a%mod;
        a=a*a%mod;
        x>>=1;
    }
    return res;
}
int max(int a,int b)
{
    if(a>b)
    {
        return a;
    }
    else
    {
        return b;
    }
}
int min(int a,int b)
{
    if(a>b)
    {
        return b;
    }
    else
    {
        return a;
    }
}
int madd(int a,int b)
{
    int ans;
    ans=(a%mod+b%mod)%mod;
    return ans;
}
int mmult(int a,int b)
{
    int ans=1;
    ans=((a%mod)*(b%mod))%mod;
    return ans%mod;
}
int modinverse(int a)
{
    return power(a,mod-2);
}
void nhi_degi()
{
    int n;cin>>n;
    int W;cin>>W;
    int weight[n+3],val[n+4];
    int sum=0;

    for(int i=1;i<=n;i++)
    {
        cin>>weight[i]>>val[i];
        sum+=val[i];
    }

    int dp[sum+2],dp1[sum+2];
    for(int i=0;i<=sum+1;i++)
    {
        dp[i]=imax;
        dp1[i]=imax;
    }
    dp[0]=imax;
    dp1[0]=0;

    for(int j=1;j<=n;j++)
    {
        for(int i=1;i<=sum;i++)
        {
            dp1[i]=dp[i];
        }
        for(int i=1;i<=sum;i++)
        {
            if(val[j]<=i)
            {
                dp[i]=min(weight[j]+dp1[i-val[j]],dp1[i]);
            }
            // dp[i]=min(dp[i],dp[i-1]);
            // dp[i]=dp1[i]
        }
    }
    int bsdk=-1;
    for(int i=1;i<=sum;i++)
    {
        if(dp[i]<=W)
        {
            bsdk=i;
        }
    }
   
    cout<<bsdk;el
}
signed main()
{
    nhi_degi();
}