Submission #288228

#	Time	Username	Problem	Language	Result	Execution time	Memory
288228		Kastanda	Aliens (IOI07_aliens)	C++11	100 / 100	2 ms	404 KiB

aliens

// M
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll n, m, nwx, nwy;
int main()
{
        scanf("%lld%lld%lld", &n, &nwx, &nwy);

        map < pair < ll , ll > , bool > MP;
        auto Query = [&](ll a, ll b){
                if (a < 1 || a > n || b < 1 || b > n)
                        return false;
                if (MP.count({a, b}))
                        return MP[make_pair(a, b)];
                printf("examine %lld %lld\n", a, b);
                fflush(stdout);
                char ss[7];
                scanf("%s", ss);
                MP[make_pair(a, b)] = ss[0] == 't';
                return (bool)(ss[0] == 't');
        };

        {
                ll lg = 0;
                while (Query(nwx - (1LL << lg), nwy))
                        lg ++;
                ll left_gap = 0;
                for (ll i = lg - 1; i >= 0; i --)
                        if (Query(nwx - left_gap - (1LL << i), nwy))
                                left_gap |= 1LL << i;

                lg = 0;
                while (Query(nwx + (1LL << lg), nwy))
                        lg ++;
                ll right_gap = 0;
                for (ll i = lg - 1; i >= 0; i --)
                        if (Query(nwx + right_gap + (1LL << i), nwy))
                                right_gap |= 1LL << i;

                m = right_gap + left_gap + 1;
                assert(m >= 3 && m & 1LL);
                nwx -= left_gap;

                lg = 0;
                while (Query(nwx, nwy - (1LL << lg)))
                        lg ++;
                ll down_gap = 0;
                for (ll i = lg - 1; i >= 0; i --)
                        if (Query(nwx, nwy - down_gap - (1LL << i)))
                                down_gap |= 1LL << i;

                nwy -= down_gap;

                while (Query(nwx - m * 2LL, nwy))
                        nwx -= m * 2LL;
                if (Query(nwx - m, nwy - m))
                        nwx -= m, nwy -= m;

                while (Query(nwx, nwy - m * 2LL))
                        nwy -= m * 2LL;

                nwx += m * 2 + m / 2;
                nwy += m * 2 + m / 2;
                printf("solution %lld %lld\n", nwx, nwy);
                fflush(stdout);
        }
        return 0;
}

Compilation message (stderr)

aliens.cpp: In function 'int main()':
aliens.cpp:8:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    8 |         scanf("%lld%lld%lld", &n, &nwx, &nwy);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
aliens.cpp: In lambda function:
aliens.cpp:19:22: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   19 |                 scanf("%s", ss);
      |                 ~~~~~^~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10