oj.uz

Submission #199450

# Submission time Handle Problem Language Result Execution time Memory
199450 2020-02-01T12:51:03 Z TadijaSebez Pipes (BOI13_pipes) C++11
93.5185 / 100
 1000 ms 80608 KB 
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
const int N=100050;
const int M=500050;
int deg[N];
ll c[N],ans[M];
vector<pair<int,int>> E[N];
bool was[N],vis[N],cyc[N];
int dep[N],mnd[N],par[N];
void No(){printf("0\n");exit(0);}
void DFS(int u,int p=0){
	vis[u]=1;
	for(auto e:E[u]){
		int v=e.first;
		if(!vis[v]){
			dep[v]=dep[u]+1;
			par[v]=u;
			DFS(v,u);
		}else if(dep[v]<dep[u] && v!=p){
			//printf("%i %i %i\n",dep[u]-dep[v],u,v);
			if((dep[u]-dep[v])%2==1)No();
			for(int w=u;w!=v;w=par[w]){
				if(cyc[w])No();
				cyc[w]=1;
			}
		}
	}
}
int main(){
	int n,m;
	scanf("%i %i",&n,&m);
	for(int i=1;i<=n;i++)scanf("%lld",&c[i]);
	map<pair<int,int>,int> idx;
	for(int i=1,u,v;i<=m;i++)scanf("%i %i",&u,&v),E[u].pb({v,i}),E[v].pb({u,i}),deg[u]++,deg[v]++,idx[{u,v}]=idx[{v,u}]=i;
	DFS(1);
	queue<int> q;
	for(int i=1;i<=n;i++)if(deg[i]==1)q.push(i);
	while(q.size()){
		int x=q.front();
		q.pop();
		was[x]=1;
		for(auto e:E[x])if(!was[e.first]){
			int y,i;tie(y,i)=e;
			deg[y]--;
			ans[i]=c[x]*2;
			c[y]-=c[x];
			c[x]=0;
			if(deg[y]==1)q.push(y);
		}
	}
	if(n!=m){
		for(int i=1;i<=n;i++)if(c[i]!=0)return 0*printf("0\n");
		for(int i=1;i<=m;i++)printf("%lld\n",ans[i]);
	}else{
		int u=-1;
		for(int i=1;i<=n;i++)if(!was[i])u=i;
		vector<int> cycle;
		function<void(int)> DFS1=[&](int u){
			was[u]=1;
			cycle.pb(u);
			for(auto e:E[u]){
				int v,i;tie(v,i)=e;
				if(!was[v]){
					//printf("add:%i %i %i\n",u,v,c[u]*2);
					ans[i]+=c[u]*2;
					c[v]-=c[u];
					c[u]=0;
					DFS1(v);
				}
			}
		};
		DFS1(u);
		int v=-1;
		for(int i:cycle)if(c[i]!=0)v=i;
		//printf("v:%i %i\n",v,c[v]);
		int flu=c[v];
		int j;
		for(int i=0;i<cycle.size();i++)if(cycle[i]==v)j=i;
		for(int i=0;i<cycle.size();i++){
			int f=cycle[(j+i)%cycle.size()],s=cycle[(j+i+1)%cycle.size()];
			ans[idx[{f,s}]]+=flu;
			//printf("add:%i %i %i\n",f,s,flu);
			flu=-flu;
		}
		for(int i=1;i<=m;i++)printf("%lld\n",ans[i]);
	}
	return 0;
}

Compilation message

pipes.cpp: In function 'int main()':
pipes.cpp:80:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=0;i<cycle.size();i++)if(cycle[i]==v)j=i;
               ~^~~~~~~~~~~~~
pipes.cpp:81:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=0;i<cycle.size();i++){
               ~^~~~~~~~~~~~~
pipes.cpp:33:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%i %i",&n,&m);
  ~~~~~^~~~~~~~~~~~~~~
pipes.cpp:34:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i=1;i<=n;i++)scanf("%lld",&c[i]);
                       ~~~~~^~~~~~~~~~~~~~
pipes.cpp:36:95: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i=1,u,v;i<=m;i++)scanf("%i %i",&u,&v),E[u].pb({v,i}),E[v].pb({u,i}),deg[u]++,deg[v]++,idx[{u,v}]=idx[{v,u}]=i;
                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
pipes.cpp:79:7: warning: 'j' may be used uninitialized in this function [-Wmaybe-uninitialized]
   int j;
       ^

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 2680 KB Output is correct
2 Correct 7 ms 2732 KB Output is correct
3 Correct 9 ms 2936 KB Output is correct
4 Correct 316 ms 24000 KB Output is correct
5 Correct 6 ms 2680 KB Output is correct
6 Correct 7 ms 2680 KB Output is correct
7 Correct 7 ms 2680 KB Output is correct
8 Correct 6 ms 2684 KB Output is correct
9 Correct 10 ms 2936 KB Output is correct
10 Correct 9 ms 2936 KB Output is correct
11 Correct 8 ms 2936 KB Output is correct
12 Correct 8 ms 2936 KB Output is correct
13 Correct 191 ms 19768 KB Output is correct
14 Correct 313 ms 23044 KB Output is correct
15 Correct 329 ms 24152 KB Output is correct
16 Correct 289 ms 20856 KB Output is correct
17 Correct 285 ms 24092 KB Output is correct
18 Correct 329 ms 24152 KB Output is correct
19 Correct 333 ms 26616 KB Output is correct
20 Correct 9 ms 2680 KB Output is correct
21 Correct 7 ms 2936 KB Output is correct
22 Correct 295 ms 24084 KB Output is correct
23 Correct 227 ms 19704 KB Output is correct
24 Correct 320 ms 24148 KB Output is correct
25 Correct 241 ms 20576 KB Output is correct

Subtask #2
63.5185185185 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 2680 KB Output is correct
2 Correct 8 ms 2936 KB Output is correct
3 Correct 217 ms 23980 KB Output is correct
4 Correct 284 ms 27896 KB Output is correct
5 Correct 283 ms 23136 KB Output is correct
6 Execution timed out 1065 ms 78264 KB Time limit exceeded
7 Correct 7 ms 2680 KB Output is correct
8 Correct 9 ms 2680 KB Output is correct
9 Correct 7 ms 2680 KB Output is correct
10 Correct 7 ms 2680 KB Output is correct
11 Correct 7 ms 2680 KB Output is correct
12 Correct 7 ms 2680 KB Output is correct
13 Correct 7 ms 2808 KB Output is correct
14 Correct 7 ms 2680 KB Output is correct
15 Correct 8 ms 2936 KB Output is correct
16 Correct 7 ms 2940 KB Output is correct
17 Correct 8 ms 2936 KB Output is correct
18 Correct 8 ms 2936 KB Output is correct
19 Correct 8 ms 2936 KB Output is correct
20 Correct 8 ms 2936 KB Output is correct
21 Correct 10 ms 3192 KB Output is correct
22 Correct 9 ms 2936 KB Output is correct
23 Correct 265 ms 23448 KB Output is correct
24 Correct 371 ms 27416 KB Output is correct
25 Correct 238 ms 24056 KB Output is correct
26 Correct 236 ms 27256 KB Output is correct
27 Correct 260 ms 27576 KB Output is correct
28 Correct 298 ms 24312 KB Output is correct
29 Correct 998 ms 71920 KB Output is correct
30 Correct 342 ms 28928 KB Output is correct
31 Correct 368 ms 29580 KB Output is correct
32 Correct 312 ms 25332 KB Output is correct
33 Correct 240 ms 25772 KB Output is correct
34 Correct 279 ms 26744 KB Output is correct
35 Correct 236 ms 27896 KB Output is correct
36 Correct 281 ms 23800 KB Output is correct
37 Execution timed out 1054 ms 80608 KB Time limit exceeded
38 Correct 342 ms 28552 KB Output is correct
39 Correct 254 ms 24568 KB Output is correct
40 Correct 348 ms 27140 KB Output is correct
41 Correct 240 ms 27512 KB Output is correct
42 Correct 265 ms 27000 KB Output is correct
43 Correct 259 ms 28156 KB Output is correct
44 Correct 243 ms 23264 KB Output is correct
45 Execution timed out 1051 ms 77372 KB Time limit exceeded
46 Correct 355 ms 29684 KB Output is correct
47 Correct 341 ms 27124 KB Output is correct
48 Correct 398 ms 29168 KB Output is correct
49 Correct 243 ms 22264 KB Output is correct
50 Correct 283 ms 26744 KB Output is correct
51 Correct 281 ms 25464 KB Output is correct
52 Correct 269 ms 24336 KB Output is correct
53 Execution timed out 1018 ms 74376 KB Time limit exceeded
54 Execution timed out 121 ms 15660 KB Time limit exceeded (wall clock)