Submission #530740

#	Time	Username	Problem	Language	Result	Execution time	Memory
530740		Killer2501	Bootfall (IZhO17_bootfall)	C++14	100 / 100	295 ms	3856 KiB

bootfall

#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define ull unsigned long long
#define pb push_back
#define pll pair<ll, ll>
#define pii pair<int, int>
#define fi first
#define se second
using namespace std;
const int N = 5e2+5;
const int M = 250;
const int mod = 1e9+7;
const ll base = 75;
const int inf = 1e9;
int n, t, b[N*N], d[N], lab[N], c[N], a[N];
int ans, tong;
ll dp[N*N];
ll m, k;
pii p[N], start, finish;
vector<int> gx[N], gy[N];
vector<pii> vi;
string s[N];
void sol()
{
    cin >> n;
    dp[0] = 1;
    for(int i = 1; i <= n; i ++)
    {
        cin >> a[i];
        for(int j = tong; j >= 0; j --)dp[j+a[i]] += dp[j];
        tong += a[i];
    }
    if((tong&1) || dp[tong>>1]==0)
    {
        cout << 0;
        return;
    }
    for(int i = 1; i <= n; i ++)
    {
        for(int j = a[i]; j <= tong; j ++)dp[j] -= dp[j-a[i]];
        tong -= a[i];
        for(int j = (tong&1); j <= tong; j += 2)
            if(dp[(tong+j)>>1])++b[j];
        for(int j = tong; j >= 0; j --)dp[j+a[i]] += dp[j];
        tong += a[i];
    }
    for(int i = 0; i < N*N; i ++)if(b[i] == n)++ans;
    cout << ans << '\n';
    for(int i = 0; i < N*N; i ++)if(b[i] == n)cout << i <<" ";
}
int main()
{
    cin.tie(0);
    cout.tie(0);
    ios_base::sync_with_stdio(0);
    #define task "test"
    if(fopen(task".inp", "r"))
	{
		freopen(task".inp", "r", stdin);
		freopen(task".out", "w", stdout);
	}
    int test = 1;
    //cin >> test;
    while(test -- > 0)sol();
    return 0;
}

Compilation message (stderr)

bootfall.cpp: In function 'int main()':
bootfall.cpp:60:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |   freopen(task".inp", "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bootfall.cpp:61:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   61 |   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