oj.uz

Submission #105731

# Submission time Handle Problem Language Result Execution time Memory
105731 2019-04-14T08:16:24 Z Pro_ktmr Fireworks (APIO16_fireworks) C++14
7 / 100
 20 ms 14592 KB 
#include"bits/stdc++.h"
using namespace std;
#define LL long long
#define REP(i, n) for(int (i)=0; (i)<(n); (i)++)
#define PB push_back
#define MP make_pair
#define MOD 1000000007

int N, M;
vector<pair<int, LL>> edge[300001];
int par[300001];
vector<pair<int, LL>> chi[300001];
vector<pair<int, int>> node;
LL a[300001] ={}, b[300001] ={};

void dfs(int now, int p){
	for(int i=0; i<edge[now].size(); i++){
		if(edge[now][i].first == p) continue;
		chi[now].PB(MP(edge[now][i].first, edge[now][i].second));
		par[edge[now][i].first] = now;
		dfs(edge[now][i].first, now);
	}
}

int d[300001] = {};
int depth(int now){
	if(now == 0) return 0;
	if(d[now] != 0) return d[now];
	return d[now] = depth(par[now]) + 1;
}

LL my_binary_search(int now, LL ans, LL ok, LL ng){
	while(abs(ok-ng) > 1){
		LL m = (ok+ng) / 2;
		LL tmp = 0;
		for(int i=0; i<chi[now].size(); i++){
			if(a[chi[now][i].first] > m) tmp += a[chi[now][i].first] - m;
			else if(b[chi[now][i].first] < m) tmp += m - b[chi[now][i].first];
		}
		if(tmp == ans) ok = m;
		else ng = m;
	}
	return ok;
}

LL func(int now, LL tmp){
	LL ans = 0;
	for(int i=0; i<chi[now].size(); i++){
		if(a[chi[now][i].first] > tmp) ans += a[chi[now][i].first] - tmp;
		else if(b[chi[now][i].first] < tmp) ans += tmp - b[chi[now][i].first];
	}
	return ans;
}

LL sanbun(int now){
	LL l = 0;
	LL r = 0;
	for(int i=0; i<chi[now].size(); i++) r = max(r, b[chi[now][i].first]);
	r++;
	//[l,r)
	while(r-l > 1){
		int m = (r+l) / 2;
		if(func(now,m-1) <= func(now,m)) r = m;
		else l = m;
	}
	return l;
}

int main(){
	scanf("%d%d", &N, &M);
	for(int i=0; i<N+M-1; i++){
		int P;
		LL C;
		scanf("%d%lld", &P, &C);
		P--;
		edge[i+1].PB(MP(P, C));
		edge[P].PB(MP(i+1, C));
	}
	
	par[0] = -1;
	dfs(0, -1);

	for(int i=0; i<N+M; i++){
		node.PB(MP(depth(i), i));
	}
	sort(node.begin(), node.end());
	reverse(node.begin(), node.end());
	
	LL ans = 0;
	for(int i=0; i<N+M; i++){
		int now = node[i].second;
		if(chi[now].size() == 0){
			a[now] = 0;
			b[now] = 0;
			continue;
		}
		for(int j=0; j<chi[now].size(); j++){
			a[chi[now][j].first] += chi[now][j].second;
			b[chi[now][j].first] += chi[now][j].second;
		}
		
		LL tmp = sanbun(now);
		LL nowAns = 0;
		for(int j=0; j<chi[now].size(); j++){
			if(tmp < a[chi[now][j].first]) nowAns += a[chi[now][j].first] - tmp;
			else if(tmp > b[chi[now][j].first]) nowAns += tmp - b[chi[now][j].first];
		}
		ans += nowAns;
		a[now] = my_binary_search(now, nowAns, tmp, -1);
		b[now] = my_binary_search(now, nowAns, tmp, 1000000000LL*300000LL);
	}

	cout << ans << endl;
}

Compilation message

fireworks.cpp: In function 'void dfs(int, int)':
fireworks.cpp:17:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0; i<edge[now].size(); i++){
               ~^~~~~~~~~~~~~~~~~
fireworks.cpp: In function 'long long int my_binary_search(int, long long int, long long int, long long int)':
fireworks.cpp:36:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=0; i<chi[now].size(); i++){
                ~^~~~~~~~~~~~~~~~
fireworks.cpp: In function 'long long int func(int, long long int)':
fireworks.cpp:48:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0; i<chi[now].size(); i++){
               ~^~~~~~~~~~~~~~~~
fireworks.cpp: In function 'long long int sanbun(int)':
fireworks.cpp:58:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0; i<chi[now].size(); i++) r = max(r, b[chi[now][i].first]);
               ~^~~~~~~~~~~~~~~~
fireworks.cpp: In function 'int main()':
fireworks.cpp:97:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0; j<chi[now].size(); j++){
                ~^~~~~~~~~~~~~~~~
fireworks.cpp:104:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0; j<chi[now].size(); j++){
                ~^~~~~~~~~~~~~~~~
fireworks.cpp:70:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &N, &M);
  ~~~~~^~~~~~~~~~~~~~~~
fireworks.cpp:74:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%lld", &P, &C);
   ~~~~~^~~~~~~~~~~~~~~~~~

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 19 ms 14464 KB Output is correct
2 Correct 18 ms 14464 KB Output is correct
3 Correct 20 ms 14464 KB Output is correct
4 Correct 18 ms 14464 KB Output is correct
5 Correct 19 ms 14464 KB Output is correct
6 Correct 17 ms 14464 KB Output is correct
7 Correct 17 ms 14592 KB Output is correct
8 Correct 15 ms 14464 KB Output is correct
9 Correct 18 ms 14464 KB Output is correct
10 Correct 17 ms 14464 KB Output is correct

Subtask #2
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 14456 KB Output is correct
2 Correct 19 ms 14464 KB Output is correct
3 Incorrect 18 ms 14464 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 19 ms 14464 KB Output is correct
2 Correct 18 ms 14464 KB Output is correct
3 Correct 20 ms 14464 KB Output is correct
4 Correct 18 ms 14464 KB Output is correct
5 Correct 19 ms 14464 KB Output is correct
6 Correct 17 ms 14464 KB Output is correct
7 Correct 17 ms 14592 KB Output is correct
8 Correct 15 ms 14464 KB Output is correct
9 Correct 18 ms 14464 KB Output is correct
10 Correct 17 ms 14464 KB Output is correct
11 Correct 18 ms 14456 KB Output is correct
12 Correct 19 ms 14464 KB Output is correct
13 Incorrect 18 ms 14464 KB Output isn't correct
14 Halted 0 ms 0 KB -

Subtask #4
0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 19 ms 14464 KB Output is correct
2 Correct 18 ms 14464 KB Output is correct
3 Correct 20 ms 14464 KB Output is correct
4 Correct 18 ms 14464 KB Output is correct
5 Correct 19 ms 14464 KB Output is correct
6 Correct 17 ms 14464 KB Output is correct
7 Correct 17 ms 14592 KB Output is correct
8 Correct 15 ms 14464 KB Output is correct
9 Correct 18 ms 14464 KB Output is correct
10 Correct 17 ms 14464 KB Output is correct
11 Correct 18 ms 14456 KB Output is correct
12 Correct 19 ms 14464 KB Output is correct
13 Incorrect 18 ms 14464 KB Output isn't correct
14 Halted 0 ms 0 KB -