Submission #717388

#	Time	Username	Problem	Language	Result	Execution time	Memory
717388		vjudge1	Table Tennis (info1cup20_tabletennis)	C++17	49 / 100	1029 ms	196776 KiB

tabletennis

#include <bits/stdc++.h>
#define endl '\n'
#define FAST ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define int ll
typedef long long ll;
using namespace std;
const int N = 15e4 + 10, mod = 1e9 + 7;
int n, k, a[N];
map<int, bool> vis;
map<int, vector<pair<int, int> > > mp;
void solve() {
    int ch1 = a[0] + a[n+k-1], ch2 = a[0] + a[n+k-2], ch3 = a[1] + a[n+k-1];
    int cnt1 = 0, cnt2 = 0, cnt3 = 0;
    for(int i = 0; i < n + k; i++) {
        if(vis[ch1 - a[i]]) cnt1++;
        if(vis[ch2 - a[i]]) cnt2++;
        if(vis[ch3 - a[i]]) cnt3++;
    }
    int num = 0;
    if(cnt1 >= cnt2 && cnt1 >= cnt3) num = ch1;
    else if(cnt2 >= cnt1 && cnt2 >= cnt3) num = ch2;
    else num = ch3;
    int dont = a[n+k-1];
    for(int i = 0; i < n + k; i++) {
        if(vis[num - a[i]]) cout << a[i] << ' ';
    }
    return;
}
// 2 + 2 = 4
// 4 + 2 = 6
void solve1() {
    vector<int> v;
    int cnt[100];
    for(int i = 0; i < 100; i++) cnt[i] = 0;
    if(n + k == 4) for(int i = 0; i < n + k; i++) v.push_back(a[i]);
    else {
        v.push_back(a[0]);
        v.push_back(a[1]);
        v.push_back(a[2]);
        v.push_back(a[n+k-1]);
        v.push_back(a[n+k-2]);
        v.push_back(a[n+k-3]);
    }
    set<int> s;
    for(int i = 0; i < v.size(); i++) {
        for(int j = 0; j < v.size(); j++) {
            s.insert(v[i] + v[j]);
        }
    }
    vector<int> nums;
    for(auto it : s) nums.push_back(it);
    int num = 0, cur = 0;
    for(int i = 0; i < n + k; i++) {
        for(int j = 0; j < nums.size(); j++) {
            if(vis[nums[j] - a[i]]) cnt[j]++;
            if(cnt[j] > cur) {
                cur = cnt[j];
                num = nums[j];
            }
        }
    }
    set<pair<int, int> > ans;
    for(int i = 0; i < n + k; i++) {
        if(vis[num - a[i]]) ans.insert({min(num-a[i], a[i]), max(num-a[i], a[i])});
    }
    vector<int> fin;
    for(auto it : ans) {
        if(fin.size() == n) break;
        fin.push_back(it.first);
        fin.push_back(it.second);
    }
    sort(fin.begin(), fin.end());
    for(int it : fin) cout << it << ' ';
    return;
}
void solve2() {
    set<int> v;
    int cnt[100];
    for(int i = 0; i < 200; i++) cnt[i] = 0;
    for(int i = 0; i < k + 1; i++) v.insert(a[i]);
    for(int i = n + k - 1; i > (n + k - 1) - k - 1; i--) v.insert(a[i]);
    set<int> s;
    for(auto i : v) {
        for(auto j : v) {
            s.insert(i + j);
        }
    }
    vector<int> nums;
    for(auto it : s) nums.push_back(it);
    int num = 0, cur = 0;
    for(int i = 0; i < n + k; i++) {
        for(int j = 0; j < nums.size(); j++) {
            if(vis[nums[j] - a[i]]) cnt[j]++;
            if(cnt[j] > cur) {
                cur = cnt[j];
                num = nums[j];
            }
        }
    }
    set<pair<int, int> > ans;
    for(int i = 0; i < n + k; i++) {
        if(vis[num - a[i]]) ans.insert({min(num-a[i], a[i]), max(num-a[i], a[i])});
    }
    vector<int> fin;
    for(auto it : ans) {
        if(fin.size() == n) break;
        fin.push_back(it.first);
        fin.push_back(it.second);
    }
    sort(fin.begin(), fin.end());
    for(int it : fin) cout << it << ' ';
    return;
}
signed main() {
    FAST;
    cin >> n >> k;
    int num = 0;
    for(int i = 0; i < n + k; i++) {
        cin >> a[i];
        vis[a[i]] = 1;
    }
    if(k == 1) {
        solve();
        return 0;
    }
    if(k == 2) {
        solve1();
        return 0;
    }
    if(k <= 20) {
        solve2();
        return 0;
    }
    for(int i = 0; i < n + k - 1; i++) {
        for(int j = i + 1; j < n + k; j++) {
            mp[a[i] + a[j]].push_back({a[i], a[j]});
            if(mp[a[i] + a[j]].size() >= n / 2) num = a[i] + a[j];
        }
    }
    vector<int> v;
    int i = 0;
    while(v.size() < n && i < mp[num].size()) {
        v.push_back(mp[num][i].first);
        v.push_back(mp[num][i].second);
        i++;
    }
    sort(v.begin(), v.end());
    for(auto it : v) {
        cout << it << ' ';
    }
}

Compilation message (stderr)

tabletennis.cpp: In function 'void solve()':
tabletennis.cpp:23:9: warning: unused variable 'dont' [-Wunused-variable]
   23 |     int dont = a[n+k-1];
      |         ^~~~
tabletennis.cpp: In function 'void solve1()':
tabletennis.cpp:45:22: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |     for(int i = 0; i < v.size(); i++) {
      |                    ~~^~~~~~~~~~
tabletennis.cpp:46:26: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |         for(int j = 0; j < v.size(); j++) {
      |                        ~~^~~~~~~~~~
tabletennis.cpp:54:26: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |         for(int j = 0; j < nums.size(); j++) {
      |                        ~~^~~~~~~~~~~~~
tabletennis.cpp:68:23: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
   68 |         if(fin.size() == n) break;
      |            ~~~~~~~~~~~^~~~
tabletennis.cpp: In function 'void solve2()':
tabletennis.cpp:92:26: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   92 |         for(int j = 0; j < nums.size(); j++) {
      |                        ~~^~~~~~~~~~~~~
tabletennis.cpp:106:23: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
  106 |         if(fin.size() == n) break;
      |            ~~~~~~~~~~~^~~~
tabletennis.cpp: In function 'int main()':
tabletennis.cpp:137:39: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
  137 |             if(mp[a[i] + a[j]].size() >= n / 2) num = a[i] + a[j];
      |                ~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~
tabletennis.cpp:142:20: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
  142 |     while(v.size() < n && i < mp[num].size()) {
      |           ~~~~~~~~~^~~
tabletennis.cpp:142:29: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  142 |     while(v.size() < n && i < mp[num].size()) {
      |                           ~~^~~~~~~~~~~~~~~~
tabletennis.cpp: In function 'void solve2()':
tabletennis.cpp:79:41: warning: iteration 100 invokes undefined behavior [-Waggressive-loop-optimizations]
   79 |     for(int i = 0; i < 200; i++) cnt[i] = 0;
      |                                  ~~~~~~~^~~
tabletennis.cpp:79:22: note: within this loop
   79 |     for(int i = 0; i < 200; i++) cnt[i] = 0;
      |                    ~~^~~~~
tabletennis.cpp:79:41: warning: 'void* __builtin_memset(void*, int, long unsigned int)' forming offset [800, 1599] is out of the bounds [0, 800] of object 'cnt' with type 'll [100]' {aka 'long long int [100]'} [-Warray-bounds]
   79 |     for(int i = 0; i < 200; i++) cnt[i] = 0;
      |                                  ~~~~~~~^~~
tabletennis.cpp:78:9: note: 'cnt' declared here
   78 |     int cnt[100];
      |         ^~~

• Subtask 1: 11 / 11
• Subtask 2: 9 / 9
• Subtask 3: 14 / 14
• Subtask 4: 15 / 15
• Subtask 5: 0 / 9
• Subtask 6: 0 / 14
• Subtask 7: 0 / 15
• Subtask 8: 0 / 13