Submission #1099745

#	Time	Username	Problem	Language	Result	Execution time	Memory
1099745		spycoderyt	Cave (IOI13_cave)	C++17	100 / 100	259 ms	1108 KiB

cave

#include "cave.h"
#include <bits/stdc++.h>
using namespace std;
void exploreCave(int n) {
    // int l = 0;
    // vector<int> v(n),a(n);
    // for(int i = 0;i<n;i++)a[i]=i;
    // while(l<n) {
    //     int ans = tryCombination(v.data());
    //     if(ans>l || ans == -1)l++;
    //     else v[l]^=1,l++;
    // }
    // answer(v.data(),a.data());

    // vector<int> v(n),a(n);
    // for(int i = 0;i<n;i++) {
    //     v[i]^=1;
    //     a[i] = tryCombination(v.data());
    //     v[i]^=1;
    // }
    // answer(v.data(),a.data());
    vector<int> v(n),a(n),d(n),tmp; // vec ans done
    for(int i = 0;i<n;i++) { // iterate over doors
        int l = 0, r = n-1; //bsearch on switch
        int res = tryCombination(v.data());
        int can = ((res > i) || (res == -1) ? 1 : 0); // 1 if up to i is open, 0 if i is closed
        while(l<r) {
            int mid = (l+r)/2;
            tmp = v;
            for(int i = l;i<=mid;i++) if(!d[i])tmp[i]^=1;
            if(can) { // want to close it
                if(tryCombination(tmp.data()) == i) r = mid;
                else l = mid+1;
            } else { // want to open it
                res = tryCombination(tmp.data());
                if(res > i || res == -1) r = mid;
                else l = mid+1;
            }
        }
        d[r]=1;
        a[r] = i;
        if(can==0)v[r]^=1;
    }
    answer(v.data(),a.data());
}

• Subtask 1: 12 / 12
• Subtask 2: 13 / 13
• Subtask 3: 21 / 21
• Subtask 4: 30 / 30
• Subtask 5: 24 / 24