Submission #1280060

#	Time	Username	Problem	Language	Result	Execution time	Memory
1280060		dosts	Colors (BOI20_colors)	C++20	9 / 100	2 ms	424 KiB

Colors

#include <bits/stdc++.h>
#define int long long
#define vi vector<int>
#define pii pair<int,int> 
#define ff first
#define ss second
#define sp << " " << 
#define all(x) x.begin(),x.end()

using namespace std;

int ask(int x) {
    cout << "? " << x << endl;
    int ans;
    cin >> ans;
    return ans;
}

void guess(int x) {
    cout << "= " << x << endl;
    exit(0);
}
void solve() {
    int n;
    cin >> n;
    if (n <= 64) {
        int ptr = 1;
        int ptr2 = n;
        int lst = -1;
        for (int i=1;i<=n;i++) {
            if (i%2) {
                int c = ask(ptr);
                if (!c && lst != -1) {
                    guess(lst-ptr+1);
                    return;
                }
                lst = ptr++;
            }else {
                int c = ask(ptr2);
                if (!c && lst!=-1) {
                    guess(ptr2-lst+1);
                    return;
                }
                lst = ptr2--;
            }
        }
        guess(1);
    }
}

signed main() {
    ios_base::sync_with_stdio(0),cin.tie(0);
    #ifdef Dodi
        freopen("in.txt","r",stdin);
        freopen("out.txt","w",stdout);
    #endif
    int t = 1;
    //cin >> t;
    while (t --> 0) solve();
}

• Subtask 1: 9 / 9
• Subtask 2: 0 / 13
• Subtask 3: 0 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 33