Submission #110541

#	Time	Username	Problem	Language	Result	Execution time	Memory
110541		Pro_ktmr	Fireworks (APIO16_fireworks)	C++14	55 / 100	789 ms	525312 KiB

fireworks

#include"bits/stdc++.h"
using namespace std;
#define LL long long
#define PB push_back
#define MP make_pair

struct f{
	LL a=0, b=0; //xが十分に大きいとき、f(x)=ax+b
	priority_queue<LL> pq; //傾きが1変わる箇所(ダブりあり)
	void push(LL x){
		pq.push(x);
		pq.push(x);
	}
	f operator+(f x){
		f ret;
		ret.a = a + x.a;
		ret.b = b + x.b;
		if(pq.size() > x.pq.size()){
			ret.pq = pq;
			while(!x.pq.empty()){
				ret.pq.push(x.pq.top());
				x.pq.pop();
			}
		}
		else{
			ret.pq = x.pq;
			while(!pq.empty()){
				ret.pq.push(pq.top());
				pq.pop();
			}
		}
		return ret;
	}
};

int N, M, par[300001], C[300001];
f node[300001];

int main(){
	scanf("%d%d", &N, &M);
	for(int i=2; i<=N+M; i++) scanf("%d%d", par+i, C+i);
	
	for(int i=N+M; i>N; i--){
		node[i].a = 1;
		node[i].b = -C[i];
		node[i].push(C[i]);

		node[par[i]] = node[par[i]] + node[i];
	}
	for(int i=N; i>1; i--){
		while(node[i].a > 1){ //傾きが1より大きい右の方は使わない
			node[i].a--;
			node[i].b += node[i].pq.top();
			node[i].pq.pop();
		}

		//このノードと親との辺の情報を追加
		LL tmp1 = node[i].pq.top();
		node[i].pq.pop();
		LL tmp0 = node[i].pq.top();
		node[i].pq.pop();
		node[i].pq.push(tmp0+C[i]);
		node[i].pq.push(tmp1+C[i]);
		node[i].b -= C[i];

		node[par[i]] = node[par[i]] + node[i];
	}
	while(node[1].a > 0){ //最小のところでは傾きが0
		node[1].a--;
		node[1].b += node[1].pq.top();
		node[1].pq.pop();
	}
	printf("%lld\n", node[1].b);
}

Compilation message (stderr)

fireworks.cpp: In function 'int main()':
fireworks.cpp:40:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &N, &M);
  ~~~~~^~~~~~~~~~~~~~~~
fireworks.cpp:41:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i=2; i<=N+M; i++) scanf("%d%d", par+i, C+i);
                            ~~~~~^~~~~~~~~~~~~~~~~~~~

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