Submission #3699

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
3699	2013-08-31T07:43:42 Z	mjy0503	Cactus? Not cactus? (kriii1_C)	C++	1 / 1	180 ms	24632 KB

C

#include <stdio.h>
#include <algorithm>
#include <string.h>
#include <vector>
#include <set>
int n,top2=-1,stack2[200001],stack[200001],top=-1,save[200001],cnt[200001];
using namespace std;
vector<int> list[200001],list2[200001];
set< pair<int,int> > edge;
bool check[100001],flag,backedge;
void back(int k){
	int i;
	stack[++top]=k;
	while(top!=-1){
		k=stack[top];
		check[k]=1;
		for(;save[k]<list[k].size();save[k]++){
			if(!check[list[k][save[k]]]){
				list2[list[k][save[k]]].push_back(k);
				edge.insert(make_pair(list[k][save[k]],k));
				stack[++top]=list[k][save[k]];
				break;
			}
			else if(edge.find(make_pair(k,list[k][save[k]]))==edge.end()){
				edge.insert(make_pair(list[k][save[k]],k));
				cnt[list[k][save[k]]]++;
				list2[list[k][save[k]]].push_back(k);
			}
		}
		if(save[k]==list[k].size()){
			top--;
			stack2[++top2]=k;
		}
		save[k]++;
	}
}
void flood(int k){
	int i,sum=0;
	stack[++top]=k;
	while(top!=-1){
		k=stack[top];
		if(!check[k])
			sum+=cnt[k];
		check[k]=1;
		for(;save[k]<list2[k].size();save[k]++){
			if(!check[list2[k][save[k]]]){
				stack[++top]=list2[k][save[k]];
				break;
			}
		}
		if(save[k]==list2[k].size())
			top--;
	}
	if(sum>=2)
		flag=1;
}
int main(){
	int m,i,a,b;
	scanf("%d %d",&n,&m);
	for(i=0;i<m;i++){
		scanf("%d %d",&a,&b);
		a--;b--;
		list[a].push_back(b);
		list[b].push_back(a);
	}
	for(i=0;i<n;i++){
		if(!check[i])
			back(i);
	}
	for(i=0;i<n;i++){
		check[i]=0;save[i]=0;
	}
	for(;top2>=0;top2--){
		backedge=0;
		if(!check[stack2[top2]])
			flood(stack2[top2]);
	}
	if(flag)
		printf("Not cactus\n");
	else
		printf("Cactus\n");
	return 0;
}

Subtask #1

1.0 / 1.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	13808 KB	Output is correct
2	Correct	0 ms	13808 KB	Output is correct
3	Correct	4 ms	14204 KB	Output is correct
4	Correct	4 ms	14204 KB	Output is correct
5	Correct	4 ms	14072 KB	Output is correct
6	Correct	4 ms	14336 KB	Output is correct
7	Correct	4 ms	14336 KB	Output is correct
8	Correct	4 ms	14204 KB	Output is correct
9	Correct	0 ms	14336 KB	Output is correct
10	Correct	116 ms	23048 KB	Output is correct
11	Correct	92 ms	21848 KB	Output is correct
12	Correct	100 ms	20540 KB	Output is correct
13	Correct	120 ms	21728 KB	Output is correct
14	Correct	128 ms	21464 KB	Output is correct
15	Correct	124 ms	22256 KB	Output is correct
16	Correct	100 ms	20672 KB	Output is correct
17	Correct	88 ms	20144 KB	Output is correct
18	Correct	172 ms	23840 KB	Output is correct
19	Correct	180 ms	24632 KB	Output is correct
20	Correct	100 ms	20808 KB	Output is correct
21	Correct	168 ms	23840 KB	Output is correct
22	Correct	140 ms	22652 KB	Output is correct
23	Correct	0 ms	13940 KB	Output is correct
24	Correct	0 ms	13808 KB	Output is correct
25	Correct	4 ms	14864 KB	Output is correct
26	Correct	136 ms	23444 KB	Output is correct
27	Correct	64 ms	18164 KB	Output is correct
28	Correct	116 ms	22256 KB	Output is correct
29	Correct	132 ms	22652 KB	Output is correct
30	Correct	124 ms	22652 KB	Output is correct
31	Correct	136 ms	22256 KB	Output is correct
32	Correct	148 ms	23444 KB	Output is correct
33	Correct	148 ms	23444 KB	Output is correct
34	Correct	156 ms	23444 KB	Output is correct