Submission #216481

# Submission time Handle Problem Language Result Execution time Memory
216481 2020-03-27T11:04:42 Z usachevd0 Street Lamps (APIO19_street_lamps) C++14
60 / 100
579 ms 31092 KB
#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define all(a) (a).begin(), (a).end()

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef long double ld;

void debug_out()
{
    cerr << endl;
}

template<typename T1, typename... T2> void debug_out(T1 A, T2... B)
{
    cerr << ' ' << A;
    debug_out(B...);
}

#ifdef DEBUG
    #define time(...) 42
    #define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
    #define debug(...) 42
#endif

template<typename T1, typename T2> bool chkmin(T1 &x, T2 y) { return y < x ? (x = y, true) : false; }
template<typename T1, typename T2> bool chkmax(T1 &x, T2 y) { return y > x ? (x = y, true) : false; }

mt19937 rng(time(0));
const int INF32 = 1e9;
const int maxN = 300005;
char a0[maxN];
pii que[maxN];

namespace btrp
{
    struct Node
    {
        int y;
        int bg, sz, last_change;
        Node *l, *r;

        Node() {}
        Node(int _bg, int _sz, int _last_change): bg(_bg), sz(_sz), last_change(_last_change), y(rng()), l(0), r(0) {}
    };

    Node* merge(Node *a, Node *b)
    {
        if (!a) return b;
        if (!b) return a;
        if (a->y > b->y)
        {
            a->r = merge(a->r, b);
            return a;
        }
        else
        {
            b->l = merge(a, b->l);
            return b;
        }
    }

    pair<Node*, Node*> split(Node *t, int x)
    {
        if (!t) return {0, 0};
        if (t->bg < x)
        {
            auto p = split(t->r, x);
            t->r = p.fi;
            return {t, p.se};
        }
        else
        {
            auto p = split(t->l, x);
            t->l = p.se;
            return {p.fi, t};
        }
    }

    void add(Node *&t, int bg, int sz, int last_change)
    {
        auto p = split(t, bg);
        t = merge(p.fi, merge(new Node(bg, sz, last_change), p.se));
    }

    void rem(Node *&t, int x)
    {
        if (!t) return;
        if (t->bg == x)
        {
            t = merge(t->l, t->r);
            return;
        }
        if (t->bg < x)
            rem(t->r, x);
        else
            rem(t->l, x);
    }

    pair<pii, int> gt(Node *t, int x)
    {
        if (!t) return {{INF32, INF32}, INF32};
        if (t->bg <= x)
        {
            auto res = gt(t->r, x);
            if (res.fi.fi > x)
                return {{t->bg, t->sz}, t->last_change};
            else
                return res;
        }
        else
        {
            return gt(t->l, x);
        }
    }

    void travel(Node *t, vector< pair<pii, int> > &a)
    {
        if (t)
        {
            travel(t->l, a);
            a.push_back(mp(mp(t->bg, t->sz), t->last_change));
            travel(t->r, a);
        }
    }
}

signed main()
{
#ifdef DEBUG
    freopen("in", "r", stdin);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);

    int n, q;
    cin >> n >> q;
    if (0 && n <= 100 && q <= 100)
    {
        char t[q + 1][n];
        memset(t, 0, sizeof(t));
        string s;
        cin >> s;
        for (int i = 0; i < n; ++i) t[0][i] = s[i] - '0';
        for (int i = 1; i <= q; ++i)
        {
            memcpy(t[i], t[i - 1], sizeof(t[i]));
            string cmd;
            cin >> cmd;
            if (cmd == "toggle")
            {
                int j;
                cin >> j;
                --j;
                t[i][j] ^= 1;
            }
            else
            {
                int l, r;
                cin >> l >> r;
                r -= 2;
                l--;
                int ans = 0;
                for (int u = 0; u < i; ++u)
                {
                    bool ok = true;
                    for (int j = l; j <= r; ++j)
                    {
                        ok &= t[u][j];
                    }
                    if (ok) ++ans;
                }
                cout << ans << '\n';
            }
        }
        exit(0);
    }
    // normal
    string tmp;
    cin >> tmp;
    for (int i = 0; i < n; ++i) a0[i] = tmp[i] - '0';
    bool all_ones = true;
    bool toggle_to_one = true;
    int last_toggle = -1;
    int first_query = -1;
    int _a[n];
    for (int i = 0; i < n; ++i) _a[i] = a0[i];
    for (int t = 1; t <= q; ++t)
    {
        string cmd;
        cin >> cmd;
        auto &q = que[t];
        if (cmd == "toggle")
        {
            last_toggle = t;
            q.se = -1;
            cin >> q.fi;
            q.fi--;
            int i = q.fi;
            _a[i] ^= 1;
            toggle_to_one &= _a[i] == 1;
        }
        else
        {
            if (first_query == -1) first_query = t;
            cin >> q.fi >> q.se;
            q.fi--;
            q.se -= 2;
            all_ones &= q.fi == q.se;
        }
    }
    if (all_ones)
    {
        int when[n], sum[n];
        memset(when, 0, sizeof(when));
        memset(sum, 0, sizeof(sum));
        for (int t = 1; t <= q; ++t)
        {
            auto &q = que[t];
            if (q.se == -1)
            {
                int i = q.fi;
                if (a0[i] == 0)
                {
                    when[i] = t;
                }
                else
                {
                    sum[i] += t - when[i];
                }
                a0[i] ^= 1;
            }
            else
            {
                int i = q.fi;
                cout << sum[i] + (a0[i] == 1 ? t - when[i] : 0) << '\n';
            }
        }
        exit(0);
    }
    if (toggle_to_one)
    {
        int when[n];
        for (int i = 0; i < n; ++i)
            if (a0[i] == 1)
                when[i] = 0;
            else
                when[i] = INF32;
        for (int t = 1; t <= q; ++t)
        {
            auto &q = que[t];
            if (q.se == -1)
            {
                int i = q.fi;
                when[i] = t;
            }
        }
        const int logN = 19;
        const int N = 1 << logN;
        int sgt[2 * N];
        fill(sgt, sgt + 2 * N, -INF32);
        for (int i = 0; i < n; ++i)
        {
            sgt[i + N] = when[i];
        }
        for (int v = N - 1; v >= 1; --v)
        {
            sgt[v] = max(sgt[v << 1], sgt[v << 1 | 1]);
        }
        for (int t = 1; t <= q; ++t)
        {
            auto &q = que[t];
            if (q.se != -1)
            {
                int l = q.fi;
                int r = q.se;
                int mx = -1e9;
                for (l += N, r += N; l <= r; l >>= 1, r >>= 1)
                {
                    if (l & 1)  chkmax(mx, sgt[l++]);
                    if (~r & 1) chkmax(mx, sgt[r--]);
                }
                cout << max(0, t - mx) << '\n';
            }
        }
        exit(0);
    }
    if (first_query == -1)
    {
        exit(0);
    }
    if (last_toggle < first_query)
    {
        btrp::Node* blocks = 0;
        int cur_bg = -1, cur_sz = -1;
        for (int i = 0; i <= n; ++i)
        {
            if (i < n && a0[i] == 1)
            {
                if (i == 0 || a0[i - 1] == 0)
                {
                    cur_bg = i;
                    cur_sz = 1;
                }
                else ++cur_sz;
            }
            else
            {
                if (cur_bg != -1 && (i == n || i > 0 && a0[i - 1] == 1))
                {
                    btrp::add(blocks, cur_bg, cur_sz, 0);
                    cur_bg = -1;
                }
            }
        }
        auto out_blocks = [&]
        {
            vector< pair<pii, int> > remaining_blocks;
            btrp::travel(blocks, remaining_blocks);
            for (auto block : remaining_blocks)
            {
                int bg = block.fi.fi;
                int sz = block.fi.se;
                int last_change = block.se;                
                debug(bg, sz, last_change);
            }
        };
//        out_blocks();
        vector< pair<pii, int> > S;
        for (int t = 1; t <= q; ++t)
        {
            auto &q = que[t];
            if (q.se == -1)
            {
                int i = q.fi;
                if (a0[i] == 0)
                {
                    bool Left = (i > 0 && a0[i - 1] == 1);
                    bool Right = (i + 1 < n && a0[i + 1] == 1);
                    if (!Left && !Right)
                    {
                        btrp::add(blocks, i, 1, t);
                    }
                    if (Left && !Right)
                    {
                        auto block = btrp::gt(blocks, i - 1);
                        int bg = block.fi.fi;
                        int sz = block.fi.se;
                        int last_change = block.se;
                        S.push_back(mp(mp(bg, bg + sz - 1), t - last_change));
                        btrp::rem(blocks, bg);
                        btrp::add(blocks, bg, sz + 1, t);                        
                    }
                    if (!Left && Right)
                    {
                        auto block = btrp::gt(blocks, i + 1);
                        int bg = block.fi.fi;
                        int sz = block.fi.se;
                        int last_change = block.se;
                        S.push_back(mp(mp(bg, bg + sz - 1), t - last_change));
                        btrp::rem(blocks, bg);
                        btrp::add(blocks, bg - 1, sz + 1, t);
                    }
                    if (Left && Right)
                    {
                        auto block1 = btrp::gt(blocks, i - 1);
                        int bg1 = block1.fi.fi;
                        int sz1 = block1.fi.se;
                        int last_change1 = block1.se;
                        S.push_back(mp(mp(bg1, bg1 + sz1 - 1), t - last_change1));
                        btrp::rem(blocks, bg1);

                        auto block2 = btrp::gt(blocks, i + 1);
                        int bg2 = block2.fi.fi;
                        int sz2 = block2.fi.se;
                        int last_change2 = block2.se;
                        S.push_back(mp(mp(bg2, bg2 + sz2 - 1), t - last_change2));
                        btrp::rem(blocks, bg2);

                        btrp::add(blocks, bg1, sz1 + 1 + sz2, t);
                    }
                }
                else
                {
                    pair<pii, int> block = btrp::gt(blocks, i);
                    int bg = block.fi.fi;
                    int sz = block.fi.se;
                    int last_change = block.se;
                    S.push_back(mp(mp(bg, bg + sz - 1), t - last_change));
                    btrp::rem(blocks, bg);
                    if (i > bg)
                        btrp::add(blocks, bg, i - bg, t);
                    if (i < bg + sz - 1)
                        btrp::add(blocks, i + 1, (bg + sz - 1) - (i + 1) + 1, t);
                }
                a0[i] ^= 1;
            }
//            debug(t);
//            out_blocks();
        }

//        for (auto e : S)
//            debug(e.fi.fi, e.fi.se, e.se);

        //
        int fnw[n + 1];
        memset(fnw, 0, sizeof(fnw));
        auto fadd = [&](int i, int d)
        {
            for (i = n - i; i <= n; i += i & -i)
                fnw[i] += d;
        };
        auto fgt = [&](int i)
        {
            int ans = 0;
            for (i = n - i; i >= 1; i -= i & -i)
                ans += fnw[i];
            return ans;
        };

        vector< pair<pii, pii> > Z;
        for (int t = 1; t <= q; ++t)
        {
            auto &q = que[t];
            if (q.se != -1)
            {
                int l = q.fi;
                int r = q.se;
                Z.push_back(mp(mp(l, r), mp(t, -1)));
            }
        }
        sort(all(S));
        sort(all(Z));
        int ptr1 = 0, ptr2 = 0;
        for (int l = 0; l < n; ++l)
        {
            while (ptr1 < S.size() && S[ptr1].fi.fi == l)
            {
                int R = S[ptr1].fi.se;
                int D = S[ptr1].se;
                ptr1++;
                fadd(R, D);
            }
            while (ptr2 < Z.size() && Z[ptr2].fi.fi == l)
            {
                int R = Z[ptr2].fi.se;
                Z[ptr2].se.se = fgt(R);
                auto block = btrp::gt(blocks, l);
                int bg = block.fi.fi;
                int sz = block.fi.se;
                int last_change = block.se;
                if (bg != INF32 && R <= bg + sz - 1)
                {
                    Z[ptr2].se.se += Z[ptr2].se.fi - last_change;
                }
                ptr2++;
            }
        }
        sort(all(Z), [&](pair<pii, pii> p1, pair<pii, pii> p2) -> bool
        {
            return p1.se.fi < p2.se.fi;
        });
        for (auto e : Z)
            cout << e.se.se << '\n';

        exit(0);
    }

    return 0;
}

Compilation message

street_lamps.cpp: In constructor 'btrp::Node::Node(int, int, int)':
street_lamps.cpp:49:21: warning: 'btrp::Node::last_change' will be initialized after [-Wreorder]
         int bg, sz, last_change;
                     ^~~~~~~~~~~
street_lamps.cpp:48:13: warning:   'int btrp::Node::y' [-Wreorder]
         int y;
             ^
street_lamps.cpp:53:9: warning:   when initialized here [-Wreorder]
         Node(int _bg, int _sz, int _last_change): bg(_bg), sz(_sz), last_change(_last_change), y(rng()), l(0), r(0) {}
         ^~~~
street_lamps.cpp: In function 'int main()':
street_lamps.cpp:318:54: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
                 if (cur_bg != -1 && (i == n || i > 0 && a0[i - 1] == 1))
                                                ~~~~~~^~~~~~~~~~~~~~~~~
street_lamps.cpp: In lambda function:
street_lamps.cpp:334:43: warning: statement has no effect [-Wunused-value]
                 debug(bg, sz, last_change);
                                           ^
street_lamps.cpp:331:21: warning: unused variable 'bg' [-Wunused-variable]
                 int bg = block.fi.fi;
                     ^~
street_lamps.cpp:332:21: warning: unused variable 'sz' [-Wunused-variable]
                 int sz = block.fi.se;
                     ^~
street_lamps.cpp:333:21: warning: unused variable 'last_change' [-Wunused-variable]
                 int last_change = block.se;                
                     ^~~~~~~~~~~
street_lamps.cpp: In function 'int main()':
street_lamps.cpp:446:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             while (ptr1 < S.size() && S[ptr1].fi.fi == l)
                    ~~~~~^~~~~~~~~~
street_lamps.cpp:453:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             while (ptr2 < Z.size() && Z[ptr2].fi.fi == l)
                    ~~~~~^~~~~~~~~~
street_lamps.cpp:325:14: warning: variable 'out_blocks' set but not used [-Wunused-but-set-variable]
         auto out_blocks = [&]
              ^~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Incorrect 5 ms 384 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 89 ms 3704 KB Output is correct
2 Correct 87 ms 3704 KB Output is correct
3 Correct 89 ms 3704 KB Output is correct
4 Correct 116 ms 7668 KB Output is correct
5 Correct 122 ms 8016 KB Output is correct
6 Correct 101 ms 7564 KB Output is correct
7 Correct 119 ms 7564 KB Output is correct
8 Correct 141 ms 9064 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 8 ms 4480 KB Output is correct
2 Correct 8 ms 4480 KB Output is correct
3 Correct 8 ms 4480 KB Output is correct
4 Correct 8 ms 4480 KB Output is correct
5 Correct 80 ms 9868 KB Output is correct
6 Correct 126 ms 10132 KB Output is correct
7 Correct 145 ms 10252 KB Output is correct
8 Correct 178 ms 11844 KB Output is correct
9 Correct 88 ms 7288 KB Output is correct
10 Correct 93 ms 7416 KB Output is correct
11 Correct 95 ms 7544 KB Output is correct
12 Correct 175 ms 10484 KB Output is correct
13 Correct 183 ms 12104 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 5 ms 384 KB Output is correct
3 Correct 5 ms 512 KB Output is correct
4 Correct 6 ms 384 KB Output is correct
5 Correct 254 ms 17832 KB Output is correct
6 Correct 328 ms 25124 KB Output is correct
7 Correct 444 ms 29324 KB Output is correct
8 Correct 579 ms 31092 KB Output is correct
9 Correct 212 ms 22432 KB Output is correct
10 Correct 183 ms 24100 KB Output is correct
11 Correct 203 ms 22432 KB Output is correct
12 Correct 195 ms 24072 KB Output is correct
13 Correct 202 ms 22408 KB Output is correct
14 Correct 186 ms 24096 KB Output is correct
15 Correct 182 ms 16556 KB Output is correct
16 Correct 178 ms 17800 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 5 ms 384 KB Output isn't correct
2 Halted 0 ms 0 KB -