Submission #470395

#	Time	Username	Problem	Language	Result	Execution time	Memory
470395		fefe	Fireworks (APIO16_fireworks)	C++17	7 / 100	6 ms	7372 KiB

fireworks

#include<bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
#define all(v) (v).begin(), (v).end()

using namespace std;
typedef long long LL;
typedef pair<int, int> pii;
typedef pair<LL, LL> pil;

const int MAXN = 300005;
int n, m;
int par[MAXN];
LL val[MAXN];
pil mid[MAXN];
vector<LL> lst[MAXN];
void udt(int i) {
	lst[par[i]].pb(mid[i].fi + val[i]);
	lst[par[i]].pb(mid[i].se + val[i]);
}
int main() {
	scanf("%d %d", &n, &m);
	for (int i = 2; i <= n + m; i++) {
		int p;
		LL v;
		scanf("%d %lld", &p, &v);
		par[i] = p;
		val[i] = v;
	}

	for (int i = n + m; i > n; i--) {
		mid[i] = pil(0, 0);
		udt(i);
	}

	for (int i = n; i >= 1; i--) {
		sort(all(lst[i]));
		mid[i].fi = lst[i][lst[i].size() / 2 - 1];
		mid[i].se = lst[i][lst[i].size() / 2];
		udt(i);
	}
	val[1] = mid[1].se;
	LL res = 0;
	for (int i = 2; i <= n + m; i++) {
		LL v = val[par[i]] - val[i];
		if (mid[i].fi > v) {
			val[i] = mid[i].fi;
			res += mid[i].fi - v;
		}
		else if (mid[i].se < v) {
			val[i] = mid[i].se;
			res += v - mid[i].se;
		}
		else {
			val[i] = v;
		}
	}
	printf("%lld\n", res);
	return 0;
}

Compilation message (stderr)

fireworks.cpp: In function 'int main()':
fireworks.cpp:23:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |  scanf("%d %d", &n, &m);
      |  ~~~~~^~~~~~~~~~~~~~~~~
fireworks.cpp:27:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |   scanf("%d %lld", &p, &v);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 0 / 19
• Subtask 3: 0 / 29
• Subtask 4: 0 / 45