Submission #962214

#	Time	Username	Problem	Language	Result	Execution time	Memory
962214		anango	Combo (IOI18_combo)	C++17	100 / 100	18 ms	2104 KiB

combo

#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
string guess_sequence(int N) {
    string p="";
    int n=press("AB");
    char first;
    if (n>=1) {
        int m=press("A");
        if (m==1) {
            first='A';
        }
        else {
            first='B';
        }

    }
    else {
        int m=press("X");
        if (m==1) {
            first='X';
        }
        else {
            first='Y';
        }
    }
    if (N==1) {
        string st;
        st.push_back(first);
        return st;
    }
    string cur(1,first);
    set<string> others={"A", "B","X","Y"};
    vector<string> v;
    others.erase(cur);
    for (auto i:others) {
        v.push_back(i);
    }
    for (int i=1; i<N-1; i++) {
        string guesseq="";
        for (int j=0; j<3; j++) {
            guesseq+=cur+v[0]+v[j];
        }
        guesseq+=cur+v[1];
        int ans=press(guesseq);
        if (ans==i) {
            cur+=v[2];
        }
        else if (ans==i+1) {
            cur+=v[1];
        }
        else {
            assert(ans==i+2);
            cur+=v[0];
        }
        //cout <<i << " " << cur.size() << endl;
    }
    string cur2 = cur;
    cur2.push_back('A');
    cur2+=cur;
    cur2.push_back('B');
    int ans = press(cur2);
    string cur3 = cur;
    cur3.push_back('A');
    cur3+=cur;
    cur3.push_back('X');
    int ans2 = press(cur3);
    int b1=ans!=N;
    int b2=ans2!=N;
   // cout << ans << " " << ans2 << endl;
    cur.push_back("ABXY"[2*b1+b2]);
    return cur;
}

• Subtask 1: 5 / 5
• Subtask 2: 95 / 95