Submission #728575

#	Time	Username	Problem	Language	Result	Execution time	Memory
728575		grogu	Thousands Islands (IOI22_islands)	C++17	6.75 / 100	45 ms	6088 KiB

islands

#include "islands.h"
#include <iostream>
#include <vector>
#include <variant>
#define dbg(x) cerr<<#x<<": "<<x<<endl
#define ll int
#define pll pair<ll,ll>
#define pb push_back
using namespace std;
#define maxn 405
ll n,m;
vector<ll> g[maxn];
ll id[maxn][maxn];

variant<bool, vector<int>> find_journey(int N, int M, vector<int> U, vector<int> V) {
    n = N;
    m = M;
    for(ll &x : U) x++;
    for(ll &x : V) x++;
    if(n==2){
        vector<vector<ll> > cnt(3);
        for(ll i = 0;i<m;i++){
            ll x = U[i],y = V[i];
            cnt[x].pb(i);
        }
        bool ok = cnt[1].size()>=2&&cnt[2].size()>=1;
        if(!ok) return ok;
        ll x = cnt[1][0],y = cnt[1][1];
        ll z = cnt[2][0];
        vector<ll> ans;
        ans.pb(x);
        ans.pb(z);
        ans.pb(y);
        ans.pb(x);
        ans.pb(z);
        ans.pb(y);
        return ans;
    }
    for(ll i = 0;i<m;i++){
        ll x = U[i],y = V[i];
        g[x].pb(y);
        g[y].pb(x);
        id[x][y] = i;
    }
    ll x = id[1][2];
    ll y = id[2][3];
    ll z = id[3][1];
    ll rx = id[2][1];
    ll ry = id[3][2];
    ll rz = id[1][3];
    vector<ll> ans;
    ans.pb(x);
    ans.pb(y);
    ans.pb(z);
    ans.pb(rz);
    ans.pb(ry);
    ans.pb(rx);
    ans.pb(z);
    ans.pb(y);
    ans.pb(x);
    ans.pb(rz);
    ans.pb(ry);
    ans.pb(rx);
    return ans;
}

Compilation message (stderr)

islands.cpp: In function 'std::variant<bool, std::vector<int, std::allocator<int> > > find_journey(int, int, std::vector<int>, std::vector<int>)':
islands.cpp:23:25: warning: unused variable 'y' [-Wunused-variable]
   23 |             ll x = U[i],y = V[i];
      |                         ^

• Subtask 1: 5 / 5
• Subtask 2: 1.75 / 5
• Subtask 3: 0 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 45