Submission #751130

#	Time	Username	Problem	Language	Result	Execution time	Memory
751130		Stickfish	Table Tennis (info1cup20_tabletennis)	C++17	61 / 100	365 ms	29256 KiB

tabletennis

#include <iostream>
#include <algorithm>
#include <map>
#include <cassert>
#include <vector>
using namespace std;

const int MAXN = 157000;

int get_bestval(vector<int> a, int k) {
    int n = a.size();
    map<int, int> mp;
    for (int i = 0; i < n; ++i) {
        int ctr = n - i - 1;
        for (int t = -k; t <= k; ++t) {
            if (ctr + t <= i || ctr + t >= n)
                continue;
            int val = a[i] + a[ctr + t];
            ++mp[val];
        }
    }
    int mxval = 0;
    int mxcnt = 0;
    for (auto [val, cnt] : mp) {
        if (mxcnt < cnt) {
            mxval = val;
            mxcnt = cnt;
        }
    }
    return mxval;
}

vector<int> get_withsum(vector<int> a, int sm) {
    int n = a.size();
    int j = n - 1;
    vector<int> ans;
    for (int i = 0; i < n; ++i) {
        while (j > i && a[i] + a[j] > sm)
            --j;
        if (a[i] + a[j] == sm) {
            ans.push_back(a[i]);
            ans.push_back(a[j]);
        }
    }
    return ans;
}

signed main() {
    int n, k;
    cin >> n >> k;
    vector<int> a(n + k);
    for (int i = 0; i < n + k; ++i) {
        cin >> a[i];
    }
    vector<int> na;
    for (int i = 0; i < k * 2 + 10 && i < n + k; ++i) {
        na.push_back(a[i]);
        na.push_back(a[n + k - i - 1]);
    }
    sort(na.begin(), na.end());
    na.resize(unique(na.begin(), na.end()) - na.begin());
    int mxval = get_bestval(na, k);
    vector<int> ans = get_withsum(a, mxval);
    while (ans.size() > n)
        ans.pop_back();
    sort(ans.begin(), ans.end());
    for (int i = 0; i < n; ++i) {
        cout << ans[i] << ' ';
    }
    cout << '\n';
}

Compilation message (stderr)

tabletennis.cpp: In function 'int main()':
tabletennis.cpp:64:23: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   64 |     while (ans.size() > n)
      |            ~~~~~~~~~~~^~~

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