Submission #152635

#	Time	Username	Problem	Language	Result	Execution time	Memory
152635		ansol4328	Cactus? Not cactus? (kriii1_C)	C++11	1 / 1	90 ms	12024 KiB

C

#include<bits/stdc++.h>

using namespace std;

int n, m;
vector<int> lst[100005];
bool visit[100005], cyc[100005];
int cnt, cur[100005], vlst[100005];
bool cactus=true;

void dfs(int v, int prev)
{
    if(cur[v]!=0){
        if(cactus){
            for(int i=cur[v] ; i<=cnt ; i++){
                if(cyc[vlst[i]]) cactus=false;
                cyc[vlst[i]]=true;
            }
        }
        return;
    }
    if(visit[v]) return;
    cnt++;
    visit[v]=true;
    cur[v]=cnt;
    vlst[cnt]=v;
    for(int i=0 ; i<lst[v].size() ; i++){
        int nxt=lst[v][i];
        if(nxt!=prev) dfs(nxt,v);
    }
    cnt--;
    cur[v]=0;
}

int main()
{
    scanf("%d %d",&n,&m);
    for(int i=1 ; i<=m ; i++){
        int x, y;
        scanf("%d %d",&x,&y);
        lst[x].push_back(y);
        lst[y].push_back(x);
    }
    for(int i=1 ; i<=n ; i++) if(!visit[i]) dfs(i,-1);
    printf("%s",cactus ? "Cactus" : "Not cactus");
    return 0;
}

Compilation message (stderr)

C.cpp: In function 'void dfs(int, int)':
C.cpp:27:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0 ; i<lst[v].size() ; i++){
                   ~^~~~~~~~~~~~~~
C.cpp: In function 'int main()':
C.cpp:37:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d",&n,&m);
     ~~~~~^~~~~~~~~~~~~~~
C.cpp:40:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d",&x,&y);
         ~~~~~^~~~~~~~~~~~~~~

• Subtask 1: 1 / 1