Submission #1104308

#	Time	Username	Problem	Language	Result	Execution time	Memory
1104308		Whisper	Bootfall (IZhO17_bootfall)	C++17	65 / 100	555 ms	2424 KiB

bootfall

#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std;
using ll = long long;

//#define int long long
#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define FORD(i, a, b) for (int i = (b); i >= (a); i --)
#define REP(i, a) for (int i = 0; i < (a); ++i)
#define REPD(i, a) for (int i = (a) - 1; i >= 0; --i)

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)


constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

/*
    Phu Trong from Nguyen Tat Thanh High School for gifted student
*/

template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-9;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }

template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-9;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }
#define MAX                     505
int nArr, sum = 0;

void add(int &x, int y){
    x += y;
    if(x >= Mod) x -= Mod;
    if(x < 0) x += Mod;
}
int dp[MAX * MAX / 2], A[MAX];
int total = 0;
void add(int x){
    for (int s = total / 2; s >= x; --s){
        add(dp[s], dp[s - x]);
    }
}
void sub(int x){
    for (int s = x; s <= total / 2; ++s){
        add(dp[s], -dp[s - x]);
    }
}

int cnt[MAX * MAX / 2];
bool vis[MAX * MAX / 2];
void process(void){
    cin >> nArr;
    for (int i = 1; i <= nArr; ++i) cin >> A[i], sum += A[i];
    total = sum;
    dp[0] = 1;
    for (int i = 1; i <= nArr; ++i) add(A[i]);

    if(sum % 2 != 0 or dp[sum / 2] == 0) return void(cout << 0);

    for (int i = 1; i <= nArr; ++i){
        sub(A[i]);
        sum -= A[i];
        vector<int> rback;
        for (int s = 0; s <= total / 2; ++s){
            if(dp[s] > 0){
                int dif = abs(sum - 2 * s);
                if(!vis[dif]){
                    vis[dif] = 1;
                    cnt[dif]++;
                    rback.emplace_back(dif);
                }
            }
        }
        for (int&v : rback) vis[v] = 0;
        add(A[i]);
        sum += A[i];
    }
    vector<int> ans;
    for (int s = 1; s < total; ++s){
        if(cnt[s] == nArr){
            ans.emplace_back(s);
        }
    }
    cout << (int)ans.size() << '\n';
    for(int&v : ans) cout << v << " ";
}
signed main(){
    #define name "Whisper"
    cin.tie(nullptr) -> sync_with_stdio(false);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    process();
    return (0 ^ 0);
}

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