Uva 562 - Dividing coins

Accepted  

#include<iostream>
#include<cstdio>
#include<cstring>
#include<map>
#include<string>
#include<vector>
#include<cmath>
#include<cctype>
#include<sstream>
#include<set>
#include<list>
#include<stack>
#include<utility>
#include<queue>
#include<algorithm>
#include<cstdlib>
// End
//..........
// Macro
#define sf scanf
#define pf printf
#define lp1(i,n) for(i=0;i<n;i++)
#define lp2(i,n) for(i=1;i<=n;i++)
#define mem(c,v) memset(c,v,sizeof(c))
#define cp(a) cout<<" "<<a<<" "
#define nl puts("")
#define sq(x) ((x)*(x))
#define all(x) x.begin(),x.end()
#define reall(x) x.rbegin(),x.rend()
#define sz size()
#define gc getchar()
#define pb push_back
#define freader freopen("input.txt","r",stdin)
// End.........

// Size
#define mx7 20000100
#define mx6 1500000
#define mx5 100005
#define mx4 1000100
#define inf 1<<30                                           //infinity value
#define eps 1e-9
#define mx 1009
#define mod 1000000007
#define pi acos(-1.0)

// Macros for Graph

#define white 1
#define gray 2
#define black 3
#define nil 0

using namespace std;

int v[1001][50005],arr[mx+9];

int knapsack(int n,int m_x)
{
    for(int i=0;i<=m_x;i++)
    {
        v[0][i]=0;
    }

    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=m_x;j++)
        {
            if(arr[i]<=j)
            {
                v[i][j] = max(v[i-1][j] , v[i-1][j-arr[i]] + arr[i]);
            }

            else
            {
                v[i][j] = v[i-1][j];
            }
        }
    }

    return v[n][m_x];
}

int main()
{
    int t;
    sf("%d",&t);

    while(t--)
    {
        mem(arr,0);
        int no_coin,sum=0;

        sf("%d",&no_coin);

        for(int i=1;i<=no_coin;i++)
        {
            sf("%d",&arr[i]);
            sum+=arr[i];
        }

        int avg = sum/2;

        int r=knapsack(no_coin,avg); //cout << sum << " " <<r; nl;

        pf("%d\n",(sum - (r*2)));
    }

    return 0;
}