Submission #108989

#	Time	Username	Problem	Language	Result	Execution time	Memory
108989		aer0park	문명 (KOI17_civilization)	C++14	19 / 100	607 ms	36980 KiB

civilization

#include <bits/stdc++.h>
#define f first
#define s second

using namespace std;

typedef long long ll;
typedef pair<ll,ll> pi;

ll n,k,p[4000004],transp[2004][2004],cnt,coj,anw,vis[4000004];
bool ck[4000004];
ll dx[]={1,-1,0,0},dy[]={0,0,1,-1};
vector<pi> ar;
queue<pi> q,wq;

ll par(int a)
{
    if(p[a]==a)
        return a;
    return p[a]=par(p[a]);
}

bool merge(ll a,ll b)    //a's par to b
{
    a=par(a),b=par(b);
    if(a!=b)
    {
        p[a]=b;
        return 1;   
    }
    return 0;
}

int main() 
{
    //ios::sync_with_stdio(false);
    //cin.tie(NULL);
    cin>>n>>k;
    for(int i=0;i<k;i++)
    {
        ll a,b;cin>>a>>b;
        ar.push_back({a,b});
    }
    for(int i=1;i<=n;i++)
        for(int j=1;j<=n;j++)
            transp[i][j]=++cnt;
    for(int i=1;i<=n*n+1;i++)
        p[i]=i;
    for(int i=0;i<k;i++)
    {
        wq.push(ar[i]); 
        ck[transp[ar[i].f][ar[i].s]]=1;
    }
    while(1)
    {
        bool flag=1;
        anw++;
        while(!wq.empty())
        {
            pi a=wq.front();
            q.push(a);
            wq.pop();
        }
        while(!q.empty())
        {
            ll nwx=q.front().f,nwy=q.front().s;
            q.pop();
            for(int i=0;i<4;i++)
            {
                ll ntx=nwx+dx[i],nty=nwy+dy[i];     
                if(ntx<1||ntx>n||nty<1||nty>n)
                    continue;
                if(ck[p[transp[ntx][nty]]])
                {
                    if(merge(transp[ntx][nty],transp[nwx][nwy]))
                    {
                    	if(vis[transp[ntx][nty]]==anw)
                    		flag=0;
						coj++;
					}    
                }
                else
                {
                    vis[transp[ntx][nty]]=anw;
					if(merge(transp[ntx][nty],transp[nwx][nwy]))
                        wq.push({ntx,nty});
                }	  
            }
        }
        if(coj==k-1)
        {
            if(flag)
                cout<<anw-1;
            else
                cout<<anw;  
            break;
        }
    }
    return 0;
}

• Subtask 1: 19 / 19
• Subtask 2: 0 / 35
• Subtask 3: 0 / 46