Submission #1327649

#	Time	Username	Problem	Language	Result	Execution time	Memory
1327649		retarde	Airplane (NOI23_airplane)	C++20	0 / 100	58 ms	22256 KiB

Main

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

#define pb push_back
#define pf push_front
#define mp make_pair
#define fi first
#define se second
#define int long long
#define all(x) (x).begin(), (x).end()

typedef long double ld;
typedef long long ll;
typedef pair<ll,ll> pll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<bool> vb;
typedef vector<vector<int>> vvi;
typedef vector<vector<bool>> vvb;
typedef vector<vector<ll>> vvll;
typedef vector<string> vs;
typedef vector<vector<string>> vvs;
typedef vector<char> vc;
typedef vector<vector<char>> vvc;
typedef map<int, int> mii;
typedef unordered_map<int, int> umii;

const int mod = 1e9 + 7;
const int inf = INTMAX_MAX;
const bool tc = false;

vi dijk(int s, int n, vvi & adj, vi & a){
    vi d(n, 1e18); d[s] = 0;
    set<pii> st; st.insert({0, s});
    while (st.size()) {
        auto cur = *st.begin();
        st.erase(st.begin());
        int node = cur.se; int dist = cur.fi;
        for (auto &neighbour : adj[node]) {
            int du = max(a[neighbour], d[node] + 1);
            if (du < d[neighbour]) {
                st.erase({d[neighbour], neighbour});
                d[neighbour] = du;
                st.insert({d[neighbour], neighbour});
            }
        }
    }
    return d;
}

inline void solve() {
    int n, m;
    cin >> n >> m;
    vi a(n); for (int i = 0; i < n; i++) cin >> a[i];
    vvi adj(n); vector<pii> es; for (int i = 0; i < m; i++) {
        int u, v;
        cin >> u >> v;
        u--; v--;
        adj[u].pb(v);
        adj[v].pb(u);
        es.pb({u, v});
        es.pb({v, u});
    }

    vi d1 = dijk(0, n, adj, a), d2 = dijk(n - 1, n, adj, a);

    int ans = 1e18;
    for (int i = 1; i < n - 1; i++) ans = min(ans, d1[i] + d2[i]);
    for (int i = 0; i < m; i++) if (a[es[i].fi] == a[es[i].se]) ans = min(ans, 1 + d1[es[i].fi] + d2[es[i].se]);
    cout << ans << '\n';
}

void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}

signed main() {
    ios::sync_with_stdio(false);
    cout.tie(0);
    cin.tie(0);
    //setIO();

    int t = 1;
    if (tc) {
        cin >> t;
    }

    while (t--) {
        solve();
    }
}

Compilation message (stderr)

Main.cpp: In function 'void setIO(std::string)':
Main.cpp:75:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   75 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:76:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   76 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 22
• Subtask 2: 0 / 10
• Subtask 3: 0 / 31
• Subtask 4: 0 / 37