Submission #35290

#	Time	Username	Problem	Language	Result	Execution time	Memory
35290		dqhungdl	Bootfall (IZhO17_bootfall)	C++14	0 / 100	0 ms	4948 KiB

bootfall

#include <bits/stdc++.h>
using namespace std;

const int mod=1e9+7;
int n,sum,a[505],C[250005],f[250005],f2[250005];
vector<int> rs;

bool Special()
{
    if(sum%2==1)
        return false;
    f[0]=1;
    for(int i=1;i<=n;i++)
        for(int j=sum;j>=a[i];j--)
            f[j]=(f[j]+f[j-a[i]])%mod;
    return (f[sum/2]>0);
}

void Check(int pos)
{
    for(int i=a[pos];i<=sum;i++)
        f[i]=(f[i]-f[i-a[pos]]+mod)%mod;
    for(int i=0;i<(sum-a[pos]+1)/2;i++)
        if(f[i]>0||f2[i]>0)
            C[sum-a[pos]-2*i]++;
    for(int i=sum;i>=a[pos];i--)
        f[i]=(f[i]+f[i-a[pos]])%mod;
}

int main()
{
    //freopen("TEST.INP","r",stdin);
    scanf("%d",&n);
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&a[i]);
        sum+=a[i];
    }
    if(Special()==false)
    {
        cout<<0;
        return 0;
    }
    for(int i=1;i<=n;i++)
        Check(i);
    for(int i=1;i<=sum;i++)
        if(C[i]==n)
            rs.push_back(i);
    printf("%d\n",int(rs.size()));
    for(int i=0;i<rs.size();i++)
        printf("%d",rs[i]);
}

Compilation message (stderr)

bootfall.cpp: In function 'int main()':
bootfall.cpp:50:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<rs.size();i++)
                  ^
bootfall.cpp:33:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
                   ^
bootfall.cpp:36:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d",&a[i]);
                          ^

• Subtask 1: 0 / 6
• Subtask 2: 0 / 7
• Subtask 3: 0 / 15
• Subtask 4: 0 / 16
• Subtask 5: 0 / 21
• Subtask 6: 0 / 35