Submission #505157

#	Time	Username	Problem	Language	Result	Execution time	Memory
505157		rainliofficial	Xoractive (IZhO19_xoractive)	C++17	88 / 100	9 ms	840 KiB

Xoractive

#include <bits/stdc++.h>
#include "interactive.h"
//#include "grader.cpp"
using namespace std;
#define ll long long
#define pii pair<int, int>
#define f first
#define s second

multiset<int> filter(vector<int>& all, vector<int>& exclude){
    multiset<int> allValues;
    for (int i : all){
        allValues.insert(i);
    }
    for (int i : exclude){
        if (allValues.find(i) != allValues.end()){
            allValues.erase(allValues.find(i));
        }
    }
    return allValues;
}
vector<int> guess(int n) {
	vector<int> ans(n);
	vector<int> allPositions(n);
    for (int i=0; i<n; i++){
        allPositions[i] = i+1;
    }
    vector<int> exludeFirst(n-1);
    for (int i=1; i<n; i++){
        exludeFirst[i-1] = i+1;
    }
    int first = ask(1);
    map<int, int> valToInd;
    vector<int> allPairwiseXor = get_pairwise_xor(allPositions);
    vector<int> excludeFirstXor = get_pairwise_xor(exludeFirst);
    multiset<int> allValues = filter(allPairwiseXor, excludeFirstXor);
    valToInd[first] = 1;
    // Look at answer indexes by bit
    int maxBits = log2(n)+1;
    for (int i=0; i<=maxBits; i++){  
        vector<int> currSet; // The set of numbers with this bit ON
        for (int j=2; j<=n; j++){
            if (j & (1<<i)){ // This bit is ON
                currSet.push_back(j);
            }
        }
        if (currSet.empty()){
            continue; 
        }
        vector<int> currSetXor = get_pairwise_xor(currSet);
        currSet.push_back(1);
        vector<int> xorWithFirst = get_pairwise_xor(currSet);
        multiset<int> currSetResult = filter(xorWithFirst, currSetXor);
        set<int> processed;
        for (int curr : currSetResult){
            if (curr == 0 || processed.find(curr) != processed.end()){
                continue;
            }
            processed.insert(curr);
            int val = curr ^ first; // Convert XOR value to orig value
            valToInd[val] += 1<<i; 
        }
    }
    for (auto cur : valToInd){
        ans[cur.second-1] = cur.first;
    }
	return ans;
}

• Subtask 1: 6 / 6
• Subtask 2: 82 / 94