Submission #522886

#	Time	Username	Problem	Language	Result	Execution time	Memory
522886		Nursik	Bootfall (IZhO17_bootfall)	C++14	13 / 100	431 ms	23884 KiB

bootfall

#include <bits/stdc++.h>

#define pb push_back
#define ll long long
#define ld long double
#define f first
#define s second
#define mp make_pair

const ll maxn = 1e3 + 1, maxm = 4e3 + 1,  maxk = 61;
const ll inf = 1000000000, mod = inf + 7, mod2 = 998244353;
const ll pa = 31, block = 400;

using namespace std;

ll n, x, y;
ll a[maxn], dp[maxn * maxn ], cnt[maxn * maxn], cnt2[maxn * maxn];
int main(){
  //  ios_base::sync_with_stdio(false);
   // cin.tie(0), cout.tie(0);
    cin >> n;
    dp[0] = 1;
    for (int i = 1; i <= n; ++i){
        cin >> a[i];
        for (int j = maxn * maxn; j >= 0; --j){
            if (dp[j] > 0){
                dp[j + a[i]] += dp[j];
            }
        }
        x += a[i];
    }
    if (x % 2 != 0 || dp[x / 2] == 0){
        cout << 0 << '\n';
        return 0;
    }
    for (int i = 1; i <= maxn * maxn; ++i){
        cnt[i] = 1;
    }
    for (int i = 1; i <= n; ++i){
        y = x - a[i];
        for (int j = 0; j <= maxn * maxn - a[i]; ++j){
            dp[j + a[i]] -= dp[j];
            dp[j + a[i]] = max(0ll, dp[j + a[i]]);
        }
        for (int j = 0; j <= maxn * maxn; ++j){
            if (dp[j] > 0){
                ll f = j, s = y - j;
                ll rz = abs(f - s);
                if (cnt[rz] == 1){
                    cnt2[rz] = 1;
                }
            }
        }
        for (int j = maxn * maxn - a[i]; j >= 0; --j){
            dp[j + a[i]] += dp[j];
        }
        for (int j = 1; j <= maxn * maxn; ++j){
            cnt[j] = cnt2[j];
            cnt2[j] = 0;
        }
    }
    vector<int> v;
    for (int i = 1; i <= maxn * maxn; ++i){
        if (cnt[i] > 0){
            v.pb(i);
        }
    }
    cout << v.size() << '\n';
    for (auto it : v){
        cout << it << " ";
    }
}

Compilation message (stderr)

bootfall.cpp: In function 'int main()':
bootfall.cpp:37:16: warning: iteration 1002000 invokes undefined behavior [-Waggressive-loop-optimizations]
   37 |         cnt[i] = 1;
      |         ~~~~~~~^~~
bootfall.cpp:36:23: note: within this loop
   36 |     for (int i = 1; i <= maxn * maxn; ++i){
      |                     ~~^~~~~~~~~~~~~~
bootfall.cpp:46:21: warning: iteration 1002001 invokes undefined behavior [-Waggressive-loop-optimizations]
   46 |             if (dp[j] > 0){
      |                 ~~~~^
bootfall.cpp:45:27: note: within this loop
   45 |         for (int j = 0; j <= maxn * maxn; ++j){
      |                         ~~^~~~~~~~~~~~~~
bootfall.cpp:58:28: warning: iteration 1002000 invokes undefined behavior [-Waggressive-loop-optimizations]
   58 |             cnt[j] = cnt2[j];
      |                      ~~~~~~^
bootfall.cpp:57:27: note: within this loop
   57 |         for (int j = 1; j <= maxn * maxn; ++j){
      |                         ~~^~~~~~~~~~~~~~
bootfall.cpp:58:20: warning: 'void* __builtin_memcpy(void*, const void*, long unsigned int)' forming offset [8016008, 8016015] is out of the bounds [0, 8016008] of object 'cnt' with type 'long long int [1002001]' [-Warray-bounds]
   58 |             cnt[j] = cnt2[j];
      |             ~~~~~~~^~~~~~~~~
bootfall.cpp:17:31: note: 'cnt' declared here
   17 | ll a[maxn], dp[maxn * maxn ], cnt[maxn * maxn], cnt2[maxn * maxn];
      |                               ^~~
bootfall.cpp:59:21: warning: 'void* __builtin_memset(void*, int, long unsigned int)' forming offset [8016008, 8016015] is out of the bounds [0, 8016008] of object 'cnt2' with type 'long long int [1002001]' [-Warray-bounds]
   59 |             cnt2[j] = 0;
      |             ~~~~~~~~^~~
bootfall.cpp:17:49: note: 'cnt2' declared here
   17 | ll a[maxn], dp[maxn * maxn ], cnt[maxn * maxn], cnt2[maxn * maxn];
      |                                                 ^~~~

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