Submission #1585627

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Source Code Expand

    #include <bits/stdc++.h>

    using namespace std;

    const int Nmax = 10006;

    char ans, a[Nmax];
    int A, B, n, i, st[Nmax], nr;

    int main()
    {
      //  freopen("input", "r", stdin);
        cin.sync_with_stdio(false);

        cin >> A >> B;

        if(A <= B)
        {
            cout << "Impossible\n";
            fflush(stdout);
            return 0;
        }

        n = A + B;
        st[nr = 1] = 0;

        for(i=1; i<n; ++i)
        {
            if(!nr)
            {
                st[++nr] = i;
                continue;
            }

            cout << "? " << st[nr] << ' ' << i << '\n';
            fflush(stdout);
            cin >> ans;

            if(ans == 'N') --nr;
                else st[++nr] = i;
        }

        for(i=0; i<n; ++i)
        {
            cout << "? " << st[nr] << ' ' << i << '\n';
            fflush(stdout);
            cin >> ans;

            a[i] = (ans == 'Y') + '0';
        }

        cout << "! " << a << '\n';
        fflush(stdout);

        return 0;
    }

Submission Info

Judge Result