Submission #13089636

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define ull unsigned ll

#define vi vector <int>
#define ii pair <int, int>
#define vii vector <ii>
#define INFLL 9e18
#define INF 2e9
#define EPS 1e-9
#define pb push_back
#define emp emplace_back
#define PI acos(-1.0)
#define endl "\n"
#define mp make_pair
#define DEBUG 0

int main ()

{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    //freopen("input.txt", "r", stdin); 
    //freopen("output.txt", "w", stdout);
    
    
   ll n, k;
   cin >> n >> k;
   
   vi town(n);

   for (auto& j:town)
   {
       cin >> j;
   }       

   vi hello;
   int cycle;
   int start;
   int aaa = town[0];
   hello.pb(aaa);
   
   while (1)
   {
       aaa = town[aaa-1];
       auto iii = find(hello.begin(), hello.end(), aaa);
       if (iii == hello.end())
       {
           hello.pb(aaa);
           continue;
       }
       else
       {
           cycle = hello.size() - (iii - hello.begin());
           start = iii - hello.begin();
           break;
       }
       

   }

   //cout << cycle << " " << start << endl;
   if (k <= start)
   {
       cout << hello[k] << endl;
       return 0;
   }
   else
   {
       k -= start;
       cout << hello[start + k%cycle - 1] << endl;
   }
   

    return 0;
}

Submission Info

Judge Result