Submission #1104668

#	Time	Username	Problem	Language	Result	Execution time	Memory
1104668		monaxia	Swap (BOI16_swap)	C++17	0 / 100	1 ms	336 KiB

swap

#include <bits/stdc++.h>
#define pb push_back
#define ppb pop_back
#define fr first
#define sc second
#define all(v) v.begin(), v.end()
#define eps (long long)(1e-9)
using namespace std;
 
using ll = long long;
using ull = unsigned long long;
using ld = long double;

const ll Mod = 1e9 + 7;

struct Node{
    int x, y, z, index;
};

void solve(){
    int n, start, end, ans = 0;
    cin >> n >> start >> end;

    vector <Node> a(n + 1);
    vector <int> v_index(n + 1, 0), v_value(3 * n + 5), cpr, cnt(3 * n + 5, 0);
    vector <vector <Node>> node(3 * n + 5);
    queue <Node> q;

    for(int i = 1; i <= n; i ++) {
        cin >> a[i].x >> a[i].y >> a[i].z;
        cpr.pb(a[i].x);
        cpr.pb(a[i].y);
        cpr.pb(a[i].z);
        a[i].index = i;
    }

    sort(all(cpr));

    for(int i = 1; i <= n; i ++) {
        a[i].x = lower_bound(all(cpr), a[i].x) - cpr.begin() + 1;
        a[i].y = lower_bound(all(cpr), a[i].y) - cpr.begin() + 1;
        a[i].z = lower_bound(all(cpr), a[i].z) - cpr.begin() + 1;

        map <int, int> appear;

        if(appear.find(a[i].x) == appear.end()) node[a[i].x].pb(a[i]), appear[a[i].x] = 1;
        if(appear.find(a[i].y) == appear.end()) node[a[i].y].pb(a[i]), appear[a[i].y] = 1;
        if(appear.find(a[i].z) == appear.end()) node[a[i].z].pb(a[i]), appear[a[i].z] = 1;
    }  

    q.push(a[start]);
    v_index[start] = 1;

    while(!q.empty()){
        int x = q.front().x, y = q.front().y, z = q.front().z, index = q.front().index;
        q.pop();

        if(index == end){
            cout << cnt[end];
            return;
        }

        v_index[index] = 1;

        if(!v_value[x]){
            v_value[x] = 1;
            for(auto& e : node[x]){
                if(v_index[e.index]) continue;

                v_index[e.index] = 1;
                cnt[e.index] = cnt[index] + 1;

                q.push(e);
            }
        }

        if(!v_value[y]){
            v_value[y] = 1;
            for(auto& e : node[y]){
                if(v_index[e.index]) continue;
                
                v_index[e.index] = 1;
                cnt[e.index] = cnt[index] + 1;

                q.push(e);
            }
        }

        if(!v_value[z]){
            v_value[z] = 1;
            for(auto& e : node[z]){
                if(v_index[e.index]) continue;
                
                v_index[e.index] = 1;
                cnt[e.index] = cnt[index] + 1;

                q.push(e);
            }
        }
    }

    cout << -1;
}   

signed main()
{
    cin.tie(0)->sync_with_stdio(0);
 
    if(fopen("blank.inp", "r")){
        freopen("blank.inp", "r", stdin);
        freopen("blank.out", "w", stdout);
    }
    
    // cout << 1; return 0;

    ll n = 1;

    cin >> n;

    while(n) {
        solve();
        n --;
        cout << "\n";
    }
 
    // cerr << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
}

Compilation message (stderr)

swap.cpp: In function 'void solve()':
swap.cpp:21:24: warning: unused variable 'ans' [-Wunused-variable]
   21 |     int n, start, end, ans = 0;
      |                        ^~~
swap.cpp: In function 'int main()':
swap.cpp:110:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  110 |         freopen("blank.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
swap.cpp:111:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  111 |         freopen("blank.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 11
• Subtask 3: 0 / 27
• Subtask 4: 0 / 20
• Subtask 5: 0 / 32