Submission #757088

#	Time	Username	Problem	Language	Result	Execution time	Memory
757088		maomao90	Worm Worries (BOI18_worm)	C++17	100 / 100	931 ms	232644 KiB

worm

// Hallelujah, praise the one who set me free
// Hallelujah, death has lost its grip on me
// You have broken every chain, There's salvation in your name
// Jesus Christ, my living hope
#include <bits/stdc++.h> 
using namespace std;

#define REP(i, s, e) for (int i = (s); i < (e); i++)
#define RREP(i, s, e) for (int i = (s); i >= (e); i--)
template <class T>
inline bool mnto(T& a, T b) {return a > b ? a = b, 1 : 0;}
template <class T>
inline bool mxto(T& a, T b) {return a < b ? a = b, 1: 0;}
typedef long long ll;
typedef long double ld;
#define FI first
#define SE second
typedef pair<int, int> ii;
typedef pair<ll, ll> pll;
typedef tuple<int, int, int> iii;
#define ALL(_a) _a.begin(), _a.end()
#define SZ(_a) (int) _a.size()
#define pb push_back
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<ii> vii;
typedef vector<iii> viii;

#ifndef DEBUG
#define cerr if (0) cerr
#endif

const int INF = 1000000005;
const ll LINF = 1000000000000000005ll;
const int MAXN = 1000005;

int query(int x, int y, int z) {
    cout << "? " << x << ' ' << y << ' ' << z << endl;
	int ans; cin >> ans;
	if (ans == -1) exit(0);
	return ans;
}

void guess(int x, int y, int z) {
    cout << "! " << x << ' ' << y << ' ' << z << endl;
	exit(0);
}

int n, m, k, q;

namespace st2 {
    const int MAXN = 1000005;
    int qry[MAXN];
    int fib[MAXN];
    int query(int x, int y, int z) {
        if (x > n) {
            return 0;
        }
        if (qry[x]) {
            return qry[x];
        }
        cout << "? " << x << ' ' << y << ' ' << z << endl;
        int ans; cin >> ans;
        if (ans == -1) exit(0);
        return qry[x] = ans;
    }
    int main() {
        fib[0] = 1; fib[1] = 2;
        int gd = -1;
        REP (i, 2, 50) {
            fib[i] = fib[i - 1] + fib[i - 2];
            if (fib[i] + 1 >= n) {
                gd = i;
                break;
            }
        }
        int lo = 1, hi = fib[gd] + 1;
        int ans = -1;
        RREP (k, gd, 2) {
            int mid1 = lo + fib[k - 2], mid2 = lo + fib[k - 1];
            assert(hi == lo + fib[k]);
            cerr << ' ' << mid1 << ' ' << mid2 << '\n';
            int l = query(mid1, 1, 1), r = query(mid2, 1, 1);
            if (l > r) {
                hi = mid2;
            } else {
                lo = mid1;
            }
        }
        assert(lo + 2 == hi);
        int l = query(lo, 1, 1), m = query(lo + 1, 1, 1), r = query(hi, 1, 1);
        if (l >= m) {
            guess(lo, 1, 1);
        } else if (m >= l && m >= r) {
            guess(lo + 1, 1, 1);
        } else {
            assert(r >= m);
            guess(hi, 1, 1);
        }
        /*
        int lo = 1, hi = n;
        while (lo < hi) {
            int mid = lo + hi + 1 >> 1;
            int l = query(mid - 1, 1, 1), m = query(mid, 1, 1);
            if (l < m) {
                lo = mid;
            } else {
                hi = mid - 1;
            }
        }
        guess(lo, 1, 1);
        */
        return 0;
    }
}

namespace st4 {
    const int MAXN = 1005;
    int qry[MAXN][MAXN];
    int query(int x, int y, int z = 1) {
        if (x > n || y > m || x <= 0 || y <= 0) {
            return 0;
        }
        if (qry[x][y]) {
            return qry[x][y];
        }
        cout << "? " << x << ' ' << y << ' ' << z << endl;
        int ans; cin >> ans;
        if (ans == -1) exit(0);
        return qry[x][y] = ans;
    }
    bool solve(int mnx, int mxx, int mny, int mxy, iii mx) {
        cerr << mnx << ' ' << mxx << ' ' << mny << ' ' << mxy << ' ' << get<0>(mx) << ' ' << get<1>(mx) << ' ' << get<2>(mx) << '\n';
        if (mxx - mnx >= mxy - mny) {
            int mid = mnx + mxx >> 1;
            ii tmx = {-1, -1};
            REP (i, mny, mxy + 1) {
                mxto(tmx, {query(mid, i), i});
            }
            if (get<0>(mx) > tmx.FI) {
                if (get<1>(mx) <= mid) {
                    return solve(mnx, mid - 1, mny, mxy, mx);
                } else {
                    return solve(mid + 1, mxx, mny, mxy, mx);
                }
            } else {
                int up = query(mid + 1, tmx.SE), bt = query(mid - 1, tmx.SE);
                if (up > tmx.FI) {
                    return solve(mid + 1, mxx, mny, mxy, {up, mid + 1, tmx.SE});
                } else if (bt > tmx.FI) {
                    return solve(mnx, mid - 1, mny, mxy, {bt, mid - 1, tmx.SE});
                } else {
                    guess(mid, tmx.SE, 1);
                    return 1;
                }
            }
        }
        int mid = mny + mxy >> 1;
        ii tmx = {-1, -1};
        REP (i, mnx, mxx + 1) {
            mxto(tmx, {query(i, mid), i});
        }
        if (get<0>(mx) > tmx.FI) {
            if (get<2>(mx) <= mid) {
                return solve(mnx, mxx, mny, mid - 1, mx);
            } else {
                return solve(mnx, mxx, mid + 1, mxy, mx);
            }
        } else {
            int up = query(tmx.SE, mid + 1), bt = query(tmx.SE, mid - 1);
            if (up > tmx.FI) {
                return solve(mnx, mxx, mid + 1, mxy, {up, tmx.SE, mid + 1});
            } else if (bt > tmx.FI) {
                return solve(mnx, mxx, mny, mid - 1, {bt, tmx.SE, mid - 1});
            } else {
                guess(tmx.SE, mid, 1);
                return 1;
            }
        }
    }
    int main() {
        assert(solve(1, n, 1, m, {-1, -1, -1}));
        return 0;
    }
}

namespace st6 {
    const int MAXN = 505;
    const int dirx[] = {1, -1, 0, 0, 0, 0}, diry[] = {0, 0, 1, -1, 0, 0}, dirz[] = {0, 0, 0, 0, 1, -1};
    mt19937 rnd(8);
    int qry[MAXN][MAXN][MAXN];
    int query(int x, int y, int z) {
        if (x > n || y > m || z > k || x <= 0 || y <= 0 || z <= 0) {
            return 0;
        }
        if (qry[x][y][z]) {
            return qry[x][y][z];
        }
        cout << "? " << x << ' ' << y << ' ' << z << endl;
        int ans; cin >> ans;
        if (ans == -1) exit(0);
        return qry[x][y][z] = ans;
    }
    int main() {
        int mx = -1, sx, sy, sz;
        REP (_, 0, q / 2) {
            int x = rnd() % n + 1, y = rnd() % m + 1, z = rnd() % k + 1;
            if (mxto(mx, query(x, y, z))) {
                sx = x; sy = y; sz = z;
            }
        }
        while (1) {
            bool fnd = 0;
            REP (d, 0, 6) {
                int nx = sx + dirx[d], ny = sy + diry[d], nz = sz + dirz[d];
                int nmx = query(nx, ny, nz);
                if (nmx > mx) {
                    fnd = 1;
                    sx = nx, sy = ny, sz = nz;
                    mx = nmx;
                    break;
                }
            }
            if (!fnd) {
                guess(sx, sy, sz);
                return 0;
            }
        }
        assert(0);
    }
}

int main() {
    cin >> n >> m >> k >> q;
    if (m == 1 && k == 1) {
        st2::main();
    } else if (k == 1) {
        st4::main();
    } else {
        st6::main();
    }
}

Compilation message (stderr)

worm.cpp: In function 'int st2::main()':
worm.cpp:79:13: warning: unused variable 'ans' [-Wunused-variable]
   79 |         int ans = -1;
      |             ^~~
worm.cpp: In function 'bool st4::solve(int, int, int, int, iii)':
worm.cpp:136:27: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  136 |             int mid = mnx + mxx >> 1;
      |                       ~~~~^~~~~
worm.cpp:159:23: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  159 |         int mid = mny + mxy >> 1;
      |                   ~~~~^~~~~
worm.cpp: In function 'int st6::main()':
worm.cpp:226:22: warning: 'sz' may be used uninitialized in this function [-Wmaybe-uninitialized]
  226 |                 guess(sx, sy, sz);
      |                 ~~~~~^~~~~~~~~~~~
worm.cpp:226:22: warning: 'sy' may be used uninitialized in this function [-Wmaybe-uninitialized]
worm.cpp:226:22: warning: 'sx' may be used uninitialized in this function [-Wmaybe-uninitialized]

• Subtask 1: 10 / 10
• Subtask 2: 22 / 22
• Subtask 3: 12 / 12
• Subtask 4: 19 / 19
• Subtask 5: 14 / 14
• Subtask 6: 23 / 23