Submission #1208731

#	Time	Username	Problem	Language	Result	Execution time	Memory
1208731		lopkus	Bootfall (IZhO17_bootfall)	C++20	100 / 100	560 ms	2872 KiB

bootfall

#include<bits/stdc++.h>
using namespace std;
#define     ll long long
#define    pll pair<ll, ll>
#define    pii pair<int, int>
#define     fi first
#define     se second
#define all(v) (v).begin(),(v).end()
#define Unique(v) sort(all(v)); (v).erase(unique(all(v)), (v).end());
const int N = 505;
const int mod = 293847109;
int n, a[N], dp[N * N], sum;
int cnt[N * N], ans;
void add(int x) {
    for (int s = sum; s >= x; s--)
        (dp[s] += dp[s - x]) %= mod;
}
void del(int x) {
    for (int s = x; s <= sum; s++)
        (dp[s] += mod - dp[s - x]) %= mod;
}
signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    #define task "task"
    if (fopen(task".INP", "r")) {
        freopen(task".INP", "r", stdin);
        freopen(task".OUT", "w", stdout);
    }
    if (fopen("task.INP", "r")) {
        freopen("task.INP", "r", stdin);
        freopen("task.OUT", "w", stdout);
    }
    cin>>n;
    for (int i = 1; i <= n; i++)
        cin>>a[i], sum += a[i];
    dp[0] = 1;
    for (int i = 1; i <= n; i++)
        add(a[i]);
    if (sum & 1 || !dp[sum / 2])
        return cout<<0, 0;
    for (int i = 1; i <= n; i++) {
        del(a[i]);
        for (int s = 0; s <= sum - a[i]; s++)
            if (dp[s]) cnt[max(0, sum - a[i] - s - s)]++;
        add(a[i]);
    }
    for (int i = 1; i <= sum; i++)
        if (cnt[i] == n) ans++;
    cout<<ans<<'\n';
    for (int i = 1; i <= sum; i++)
        if (cnt[i] == n) cout<<i<<' ';
    cerr<<setprecision(3)<<fixed<<"Time elapsed: "<< 1.0 * clock() / CLOCKS_PER_SEC <<"s\n";
}

Compilation message (stderr)

bootfall.cpp: In function 'int main()':
bootfall.cpp:27:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |         freopen(task".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bootfall.cpp:28:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |         freopen(task".OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
bootfall.cpp:31:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 |         freopen("task.INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bootfall.cpp:32:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |         freopen("task.OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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