Submission #366141

#	Time	Username	Problem	Language	Result	Execution time	Memory
366141		nicolaalexandra	Bootfall (IZhO17_bootfall)	C++14	28 / 100	1092 ms	122988 KiB

bootfall

#include <bits/stdc++.h>
#define DIM 502
using namespace std;

bool dp_left[DIM][DIM*DIM],dp_right[DIM][DIM*DIM],dp[DIM];
int v[DIM],f[DIM*DIM];
vector <int> sol,w,w2;
int n,i,j,sum_total;

int main (){

    //ifstream cin ("date.in");
    //ofstream cout ("date.out");

    cin>>n;
    for (i=1;i<=n;i++){
        cin>>v[i];
        sum_total += v[i];
    }

    if (sum_total % 2){
        cout<<"0";
        return 0;
    }

    dp[0] = 1;
    for (i=1;i<=n;i++){
        for (j=sum_total-v[i];j>=0;j--){
            if (dp[j])
                dp[j+v[i]] = 1;
        }
    }

    if (!dp[sum_total/2]){
        cout<<"0";
        return 0;
    }

    dp_left[0][0] = 1;
    for (i=1;i<=n;i++){
        memcpy (dp_left[i],dp_left[i-1],sizeof dp_left[i-1]);
        for (j=sum_total-v[i];j>=0;j--){
            if (dp_left[i][j])
                dp_left[i][j+v[i]] = 1;
        }
    }

    dp_right[n+1][0] = 1;
    for (i=n;i;i--){
        memcpy (dp_right[i],dp_right[i+1],sizeof dp_right[i+1]);
        for (j=sum_total-v[i];j>=0;j--){
            if (dp_right[i][j])
                dp_right[i][j+v[i]] = 1;
        }
    }


    for (i=1;i<=n;i++){

        w.clear(); w2.clear();
        for (int j=0;j<=sum_total;j++){
            if (dp_left[i-1][j])
                w.push_back(j);
            if (dp_right[i+1][j])
                w2.push_back(j);
        }

        int sum = sum_total - v[i];
        for (j=1;j<=sum_total;j++){
            if ( (sum + j)%2 )
                continue;

            int val = (sum + j)/2; /// exista suma asta?
            if (dp_left[i-1][val] || dp_right[i+1][val]){
                f[j]++;
                continue;
            }

            int ok = 0;
            for (auto it : w){
                if (it > val)
                    break;

                if (dp_right[i+1][val-it-j]){
                    f[j]++;
                    ok = 1;
                    break;
                }
            }
            if (ok)
                continue;

            for (auto it : w2){
                if (it > val)
                    break;
                if (dp_left[i-1][val-it-j]){
                    f[j]++;
                    break;
                }}}}

    for (i=1;i<=sum_total;i++){
        if (f[i] == n)
            sol.push_back(i);
    }

    cout<<sol.size()<<"\n";
    for (auto it : sol)
        cout<<it<<" ";

    return 0;
}

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