Submission #363231

#	Time	Username	Problem	Language	Result	Execution time	Memory
363231		Tenis0206	Shell (info1cup18_shell)	C++11	100 / 100	592 ms	81512 KiB

shell

#include <bits/stdc++.h>

using namespace std;
const int Mod = 1e9+7;
int n,m,p,spc[1000005];
long long lvl[1000005],cnt[1000005];
bool sel[1000005];
vector<int> G[1000005],IN[1000005],d;
void dfs(int x)
{
    sel[x]=true;
    for(auto it : G[x])
    {
        if(!sel[it])
        {
            dfs(it);
        }
    }
    d.push_back(x);
}
void topsort()
{
    dfs(1);
    reverse(d.begin(),d.end());
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>m>>p;
    for(int i=1;i<=p;i++)
    {
        int x;
        cin>>x;
        spc[x]=i;
    }
    for(int i=1;i<=m;i++)
    {
        int x,y;
        cin>>x>>y;
        G[x].push_back(y);
        IN[y].push_back(x);
    }
    topsort();
    memset(sel,false,sizeof(sel));
    cnt[1]=1;
    for(auto nod : d)
    {
        sel[nod]=true;
        int tofind = 0;
        if(spc[nod])
        {
            lvl[nod]=spc[nod];
        }
        for(auto it : IN[nod])
        {
            if(!spc[nod] && lvl[it]>lvl[nod])
            {
                lvl[nod]=lvl[it];
                cnt[nod]=0;
            }
            if(!spc[nod] && lvl[it]==lvl[nod])
            {
                cnt[nod]+=cnt[it];
                cnt[nod]%=Mod;
            }
            if(spc[nod] && lvl[it]==lvl[nod]-1)
            {
                cnt[nod]+=cnt[it];
                cnt[nod]%=Mod;
            }
        }
    }
    if(lvl[n]==p)
    {
        cout<<cnt[n]%Mod<<'\n';
        return 0;
    }
    cout<<0<<'\n';
    return 0;
}

Compilation message (stderr)

shell.cpp: In function 'int main()':
shell.cpp:50:13: warning: unused variable 'tofind' [-Wunused-variable]
   50 |         int tofind = 0;
      |             ^~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 45 / 45
• Subtask 3: 20 / 20
• Subtask 4: 25 / 25