Submission #960593

# Submission time Handle Problem Language Result Execution time Memory
960593 2024-04-10T16:32:39 Z TAhmed33 Longest Trip (IOI23_longesttrip) C++17
Compilation error
0 ms 0 KB
#include "longesttrip.h"
#include <bits/stdc++.h>
using namespace std;
bool adj2[256][256];
int cnt;
bool are_connected (vector <int> x, vector <int> y) {
    bool flag = 0;
    for (int i = 0; i < (int)x.size(); i++) {
        for (int j = 0; j < (int)y.size(); j++) {
            flag |= adj2[x[i]][y[j]];
        }
    }
    return flag;
}
vector <int> tree[256];
bool vis[256];
vector <int> x;
int p[256];
set <int> unvis;
void dfs (int pos) {
    vis[pos] = 1; x.push_back(pos); unvis.erase(pos);
    while (true) {
        vector <int> t; for (auto i : unvis) t.push_back(i);
        int l = 0, r = (int)t.size() - 1, ans = -1;
        while (l <= r) {
            int mid = (l + r) / 2;
            vector <int> g;
            for (int i = 0; i <= mid; i++) g.push_back(t[i]);
            cnt++; assert(cnt <= 3000);
            if (are_connected({pos}, g)) {
                r = mid - 1; ans = mid; 
            } else {
                l = mid + 1;
            }
        }
        if (ans == -1) break;
        tree[pos].push_back(t[ans]);
        p[t[ans]] = pos;
        dfs(t[ans]);
    }
}
int get (int x) {
    if (tree[x].empty()) return x;
    return get(tree[x][0]);
}
vector <int> longest_trip (int n, int d) {
    cnt = 0;
    unvis.clear(); for (int i = 0; i < n; i++) unvis.insert(i);
    for (int i = 0; i < n; i++) tree[i].clear();
    memset(p, -1, sizeof(p));
    memset(vis, 0, sizeof(vis));
    x.clear(); dfs(0);
    if (!unvis.empty()) {
        vector <int> ret = x;
        for (int i = 0; i < n; i++) {
            if (!vis[i]) {
                x.clear(); dfs(i);
                if ((int)x.size() > (int)ret.size()) ret = x;
            }
        }
        return ret;
    }
    int pos = -1;
    for (int i = 0; i < n; i++) {
        if ((int)tree[i].size() == 2) {
            pos = i;
        }
    }
    if (pos == -1) return x;
    int u = get(tree[pos][0]), v = get(tree[pos][1]);
    if (p[pos] != -1 && !are_connected({p[pos]}, {u})) {
        swap(u, v); swap(tree[pos][0], tree[pos][1]);
    }
    u = tree[pos][0], v = tree[pos][1];
    while (!x.empty() && x.back() != p[pos]) x.pop_back();
    vector <int> l;
    while (true) {
        l.push_back(u);
        if (tree[u].empty()) break;
        u = tree[u][0];
    }
    reverse(l.begin(), l.end());
    for (auto i : l) x.push_back(i);
    x.push_back(pos);
    while (true) {
        x.push_back(v);
        if (tree[v].empty()) break;
        v = tree[v][0];
    }
    return x;   
}
mt19937 rng (chrono::steady_clock::now().time_since_epoch().count());
int random (int l, int r) {
    return uniform_int_distribution <int> (l, r) (rng);
}
int main () {   
/*    int n; cin >> n;
    for (int i = 1; i < n; i++) {
        for (int j = 0; j < i; j++) {
            int x; cin >> x;
            adj2[i][j] = adj2[j][i] = x;
        }
    }
    auto z = longest_trip(n, 1);
    for (auto i : z) cout << i << " ";
    cout << '\n';
    return 0;*/
    while (true) {
        vector <int> x, y;
        int n = random(1, 5);
        for (int i = 0; i < n; i++) {
            if (random(1, 2) == 1) x.push_back(i);
            else y.push_back(i);
        }
        memset(adj2, 0, sizeof(adj2));
        for (int i = 0; i < (int)x.size(); i++) {
            for (int j = i + 1; j < (int)x.size(); j++) {
                adj2[x[i]][x[j]] = adj2[x[j]][x[i]] = 1;
            }
        }
        for (int i = 0; i < (int)y.size(); i++) {
            for (int j = i + 1; j < (int)y.size(); j++) {
                adj2[y[i]][y[j]] = adj2[y[j]][y[i]] = 1;
            }
        }
        vector <pair <int, int>> dd;
        bool flag = 0;
        for (int i = 0; i < (int)x.size(); i++) {
            for (int j = 0; j < (int)y.size(); j++) {
                if (random(1, 2) == 1) {
                    adj2[x[i]][y[j]] = adj2[y[j]][x[i]] = 1;
                    flag = 1;
                }
            }
        }
        auto z = longest_trip(n, 1);
        if (flag) {
            if ((int)z.size() != n) {
                cout << n << '\n';
                for (int i = 1; i < n; i++) {
                    for (int j = 0; j < i; j++) {
                        cout << adj2[i][j] << " ";
                    }
                    cout << '\n';
                }
                return 0;
            }
        } else {
            if ((int)z.size() != max((int)x.size(), (int)y.size())) {
                cout << n << '\n';
                for (int i = 1; i < n; i++) {
                    for (int j = 0; j < i; j++) {
                        cout << adj2[i][j] << " ";
                    }
                    cout << '\n';
                }
                return 0;
            }
        }
    }
}

Compilation message

/usr/bin/ld: /tmp/ccPrsuLd.o: in function `are_connected(std::vector<int, std::allocator<int> >, std::vector<int, std::allocator<int> >)':
stub.cpp:(.text+0xc0): multiple definition of `are_connected(std::vector<int, std::allocator<int> >, std::vector<int, std::allocator<int> >)'; /tmp/ccLcrDrf.o:longesttrip.cpp:(.text+0x220): first defined here
/usr/bin/ld: /tmp/ccPrsuLd.o: in function `main':
stub.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccLcrDrf.o:longesttrip.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status