Submission #777833

#	Time	Username	Problem	Language	Result	Execution time	Memory
777833		JoenPoenMan	Finding Routers (IOI20_routers)	C++17	100 / 100	2 ms	596 KiB

routers

#include "routers.h"
#include <bits/stdc++.h>

using namespace std;

unordered_map<int, int> dp;

std::vector<int> find_routers(int l, int n, int q) {
    std::vector<int> sna;
    int curr = n-1;
    int low = 0, high = l, mid;
    while (curr != 0) {
        while (low != high) {
            mid = (low+high+1)/2;
            int res;
            if (dp.find(mid) != dp.end()) res = dp[mid];
            else {
                res = use_detector(mid);
                dp[mid] = res;
            }
            if (res >= curr) high = mid-1;
            else low = mid;
        }
        sna.push_back(low);
        high = l;
        low = 0;
        curr--;
    }
    vector<int> ans;
    ans.push_back(0);
    for (int i = sna.size()-1; i >= 0; i--) {
        ans.push_back(2*sna[i] - ans.back());
    }

    return ans;
}

• Subtask 1: 16 / 16
• Subtask 2: 21 / 21
• Subtask 3: 23 / 23
• Subtask 4: 40 / 40