Submission #90664

#	Time	Username	Problem	Language	Result	Execution time	Memory
90664		314rate	007 (CEOI14_007)	C++14	30 / 100	605 ms	73212 KiB

007

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;

const int N=2000000+5;

int n;
int m;
int s,d,a,b;

int di[2][N];

vector<int>g[N];

void build(int k,int go)
{
    for(int j=0;j<N;j++)
    {
        di[k][j]=-1;
    }
    di[k][go]=0;
    queue<int>q;
    q.push(go);
    while(!q.empty())
    {
        int nod=q.front();
        q.pop();
        for(auto &nou:g[nod])
        {
            if(di[k][nou]==-1)
            {
                di[k][nou]=1+di[k][nod];
                q.push(nou);
            }
        }
    }
}

int main()
{
   // freopen("input","r",stdin);
   // freopen("output","w",stdout);
    cin>>n>>m;
    cin>>s>>d>>a>>b;
    for(int i=1;i<=m;i++)
    {
        int x,y;
        cin>>x>>y;
        g[x].push_back(y);
        g[y].push_back(x);
    }
    build(0,s);
    build(1,d);
    int a1=di[0][a],a2=di[0][b];
    int b1=di[1][a],b2=di[1][b];
    int x1=b1-a1;
    int x2=b2-a2;
    int ans;
    if(x1!=x2)
    {
        ans=min(x1,x2);
    }
    else
    {
        ans=x1-1;
    }
    if(ans<-1)
    {
        ans=-1;
    }
    cout<<ans<<"\n";
    return 0;
}
/**


**/

• Subtask 1: 9 / 30
• Subtask 2: 21 / 70