답안 #409745

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
409745 2021-05-21T12:49:06 Z Kerim 구슬과 끈 (APIO14_beads) C++17
28 / 100
981 ms 3180 KB
#include "bits/stdc++.h"
#define MAXN 100009
#define INF 1000000007
#define mp(x,y) make_pair(x,y)
#define all(v) v.begin(),v.end()
#define pb(x) push_back(x)
#define wr cout<<"----------------"<<endl;
#define ppb() pop_back()
#define tr(ii,c) for(__typeof((c).begin()) ii=(c).begin();ii!=(c).end();ii++)
#define ff first
#define ss second
#define my_little_dodge 46
#define debug(x)  cerr<< #x <<" = "<< x<<endl;
using namespace std;

typedef long long ll;
typedef pair<int,int> PII;
template<class T>bool umin(T& a,T b){if(a>b){a=b;return 1;}return 0;}
template<class T>bool umax(T& a,T b){if(a<b){a=b;return 1;}return 0;}
int dp[MAXN][2];
vector<PII>adj[MAXN];
void dfs(int nd,int pr=-1,int w_p=-1){
	dp[nd][0]=0;int mx=-INF,mx1=-INF;
	for(int i=0;i<int(adj[nd].size());i++){
		int to=adj[nd][i].ff;
		int w=adj[nd][i].ss;
		if(to==pr)continue;
		dfs(to,nd,w);
		w+=dp[to][0]-dp[to][1];
		dp[nd][0]+=dp[to][1];
		if(mx<w) mx1=mx,mx=w;
		else umax(mx1,w);
	}
	if(~pr)dp[nd][1]=dp[nd][0]+max(0,mx+w_p);
	else dp[nd][0]+=max(0,mx+mx1);
}
int main(){
    //freopen("file.in", "r", stdin);
    int n;
    scanf("%d",&n);
    for(int i=0;i<n-1;i++){
    	int u,v,w;
		scanf("%d%d%d",&u,&v,&w);
		adj[u].pb(mp(v,w));
		adj[v].pb(mp(u,w));	
    }int ans=0;
    vector<int>roots;
    for(int i=1;i<=n;i++)roots.pb(i);
    int k=rand()%10+1;
    while(k--)
    	random_shuffle(all(roots));
    for(int i=0;i<n;i++){
    	if((double)clock()/CLOCKS_PER_SEC>0.98)break;
		dfs(roots[i]);
		umax(ans,dp[roots[i]][0]);
	}
    printf("%d\n",ans);
	return 0;
}

Compilation message

beads.cpp: In function 'int main()':
beads.cpp:40:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   40 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
beads.cpp:43:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   43 |   scanf("%d%d%d",&u,&v,&w);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2636 KB Output is correct
2 Correct 2 ms 2636 KB Output is correct
3 Correct 2 ms 2648 KB Output is correct
4 Correct 2 ms 2636 KB Output is correct
5 Correct 2 ms 2636 KB Output is correct
6 Correct 2 ms 2636 KB Output is correct
7 Correct 2 ms 2636 KB Output is correct
8 Correct 3 ms 2636 KB Output is correct
9 Correct 3 ms 2636 KB Output is correct
10 Correct 2 ms 2636 KB Output is correct
11 Correct 2 ms 2636 KB Output is correct
12 Correct 2 ms 2636 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2636 KB Output is correct
2 Correct 2 ms 2636 KB Output is correct
3 Correct 2 ms 2648 KB Output is correct
4 Correct 2 ms 2636 KB Output is correct
5 Correct 2 ms 2636 KB Output is correct
6 Correct 2 ms 2636 KB Output is correct
7 Correct 2 ms 2636 KB Output is correct
8 Correct 3 ms 2636 KB Output is correct
9 Correct 3 ms 2636 KB Output is correct
10 Correct 2 ms 2636 KB Output is correct
11 Correct 2 ms 2636 KB Output is correct
12 Correct 2 ms 2636 KB Output is correct
13 Correct 2 ms 2636 KB Output is correct
14 Correct 2 ms 2636 KB Output is correct
15 Correct 2 ms 2636 KB Output is correct
16 Correct 3 ms 2636 KB Output is correct
17 Correct 3 ms 2636 KB Output is correct
18 Correct 3 ms 2636 KB Output is correct
19 Correct 3 ms 2636 KB Output is correct
20 Correct 3 ms 2636 KB Output is correct
21 Correct 3 ms 2636 KB Output is correct
22 Correct 3 ms 2636 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2636 KB Output is correct
2 Correct 2 ms 2636 KB Output is correct
3 Correct 2 ms 2648 KB Output is correct
4 Correct 2 ms 2636 KB Output is correct
5 Correct 2 ms 2636 KB Output is correct
6 Correct 2 ms 2636 KB Output is correct
7 Correct 2 ms 2636 KB Output is correct
8 Correct 3 ms 2636 KB Output is correct
9 Correct 3 ms 2636 KB Output is correct
10 Correct 2 ms 2636 KB Output is correct
11 Correct 2 ms 2636 KB Output is correct
12 Correct 2 ms 2636 KB Output is correct
13 Correct 2 ms 2636 KB Output is correct
14 Correct 2 ms 2636 KB Output is correct
15 Correct 2 ms 2636 KB Output is correct
16 Correct 3 ms 2636 KB Output is correct
17 Correct 3 ms 2636 KB Output is correct
18 Correct 3 ms 2636 KB Output is correct
19 Correct 3 ms 2636 KB Output is correct
20 Correct 3 ms 2636 KB Output is correct
21 Correct 3 ms 2636 KB Output is correct
22 Correct 3 ms 2636 KB Output is correct
23 Correct 726 ms 2912 KB Output is correct
24 Correct 708 ms 2912 KB Output is correct
25 Correct 711 ms 2908 KB Output is correct
26 Incorrect 981 ms 3180 KB Output isn't correct
27 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2636 KB Output is correct
2 Correct 2 ms 2636 KB Output is correct
3 Correct 2 ms 2648 KB Output is correct
4 Correct 2 ms 2636 KB Output is correct
5 Correct 2 ms 2636 KB Output is correct
6 Correct 2 ms 2636 KB Output is correct
7 Correct 2 ms 2636 KB Output is correct
8 Correct 3 ms 2636 KB Output is correct
9 Correct 3 ms 2636 KB Output is correct
10 Correct 2 ms 2636 KB Output is correct
11 Correct 2 ms 2636 KB Output is correct
12 Correct 2 ms 2636 KB Output is correct
13 Correct 2 ms 2636 KB Output is correct
14 Correct 2 ms 2636 KB Output is correct
15 Correct 2 ms 2636 KB Output is correct
16 Correct 3 ms 2636 KB Output is correct
17 Correct 3 ms 2636 KB Output is correct
18 Correct 3 ms 2636 KB Output is correct
19 Correct 3 ms 2636 KB Output is correct
20 Correct 3 ms 2636 KB Output is correct
21 Correct 3 ms 2636 KB Output is correct
22 Correct 3 ms 2636 KB Output is correct
23 Correct 726 ms 2912 KB Output is correct
24 Correct 708 ms 2912 KB Output is correct
25 Correct 711 ms 2908 KB Output is correct
26 Incorrect 981 ms 3180 KB Output isn't correct
27 Halted 0 ms 0 KB -