Submission #786833

#	Time	Username	Problem	Language	Result	Execution time	Memory
786833		drdilyor	Wombats (IOI13_wombats)	C++17	55 / 100	20027 ms	16716 KiB

wombats

#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")

#include<bits/stdc++.h>
#include "wombats.h"
using namespace std;
using ll = long long;
const int inf = 1e9 + 1000;

struct SegmentTree {
    using T = int;
    using S = int;
    const T id = inf;
    inline T single(S v) { return v; }

    T merge(const T& l, const T& r) {
        return min(l, r);
    }

    int n;
    vector<T> tree;

    SegmentTree(int n) : n(n) {
        tree.resize(n * 2, id);
        build();
    }
    SegmentTree(vector<S> arr) : n(arr.size()) {
        tree.resize(n * 2, id);
        for (int i = 0; i < n; i++) {
            tree[i + n] = single(arr[i]);
        }
        build();
    }

    void build() {
        for (int i = n-1; i >= 1; i--) {
            tree[i] = merge(tree[i*2], tree[i*2 + 1]);
        }
    }

    void update(int i, S v) {
        tree[i+=n] = single(v);
        for (i /= 2; i >= 1; i/= 2)
            tree[i] = merge(tree[i*2], tree[i*2+1]);
    }

    T query(int l, int r) {
        T left = id, right = id;
        l += n;
        r += n;
        while (l <= r) {
            if (l % 2 == 1) left = merge(left, tree[l++]);
            if (r % 2 == 0) right = merge(right, tree[r--]);
            l /= 2; r /= 2;
        }
        return merge(left, right);
    }

    int find_first(function<bool(T&)> predicate, int last = 0) {
        int v = 1;
        while (v < n) {
            if (predicate(tree[v*2 + last])) v = v*2 + last;
            else if (predicate(tree[v*2 + !last])) v = v*2 + !last;
            else return -1;
        }
        return v;
    }
};

struct Fenwick {
    int n;
    vector<int> tree;

    Fenwick() = default;
    Fenwick(int n) : n(n) {
        tree.assign(n, 0);
    }

    void inc(int pos, ll val) {
        for (; pos < n; pos |= (pos + 1)) {
            tree[pos] += val;
        }
    }

    int sum(int r) { // [0, r]
        ll ans = 0;
        for (; r >= 0; r = (r & (r + 1)) - 1) {
            ans += tree[r];
        }
        return ans;
    }

    int sum(int l, int r) { // [l, r]
        return sum(r) - sum(l - 1);
    }

    int operator[](int index) {
        return sum(index) - sum(index-1);
    };
};

int r, c;
vector<Fenwick> level;
vector<Fenwick> pass;
vector<vector<ll>> dist;

vector<int> dirty;

void update(int v2) {
    if (!dirty[v2]) return;
    dirty[v2] = 0;

    vector<int> dp(c, inf);
    dp[v2] = 0;
    SegmentTree st(c);
    for (int i = r-1; i >= 0; i--) {

        auto sum = [&](int r) {
            return level[i].sum(r);
        };

        vector<int> ndp(dp);

        for (int j = 0; j < c; j++) {
            int mn = st.query(0, j-1);
            ndp[j] = min(ndp[j], mn + sum(j-1));
            st.update(j, dp[j] - sum(j - 1));
        }

        for (int j = c-1; j >= 0; j--) {
            int mn = st.query(j+1, c-1);
            ndp[j] = min(ndp[j], mn - sum(j-1));
            st.update(j, dp[j] + sum(j-1));
        }

        for (int j = 0; j < c; j++) {
            if (i) ndp[j] += pass[i-1][j];
        }

        dp.swap(ndp);
    }
    for (int v1 = 0; v1 < c; v1++)
        dist[v1][v2] = dp[v1];
}

void init(int32_t r, int32_t c, int32_t h[5000][200], int32_t v[5000][200]) {
    ::r = r;
    ::c = c;
    level.resize(r);
    for (int i = 0; i < r; i++) {
        level[i] = Fenwick(c);
        for (int j = 0; j < c-1; j++) {
            level[i].inc(j, h[i][j]);
        }
    }

    pass.resize(r-1);
    for (int i = 0; i < r-1; i++) {
        pass[i] = Fenwick(c);
        for (int j = 0; j < c; j++) {
            pass[i].inc(j, v[i][j]);
        }
    }
    dirty.assign(c, 1);
    dist = vector(c, vector(c, 0ll));
}

void changeH(int32_t p, int32_t q, int32_t w) {
    level[p].inc(q, w - level[p][q]);
    dirty.assign(c, 1);
}

void changeV(int32_t p, int32_t q, int32_t w) {
    pass[p].inc(q, w - pass[p][q]);
    dirty.assign(c, 1);
}

int32_t escape(int32_t v1, int32_t v2) {
    update(v2);
    return dist[v1][v2];
}

Compilation message (stderr)

grader.c: In function 'int main()':
grader.c:15:6: warning: variable 'res' set but not used [-Wunused-but-set-variable]
   15 |  int res;
      |      ^~~

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 16 / 16
• Subtask 4: 18 / 18
• Subtask 5: 0 / 21
• Subtask 6: 0 / 24