Submission #711354

#	Time	Username	Problem	Language	Result	Execution time	Memory
711354		elkernos	The short shank; Redemption (BOI21_prison)	C++17	100 / 100	1676 ms	86548 KiB

prison

// Sylwia Sapkowska
#include <bits/stdc++.h>
#pragma GCC optimize("O3", "unroll-loops")
using namespace std;
 
void __print(int x) { cerr << x; }
void __print(long long x) { cerr << x; }
void __print(long double x) { cerr << x; }
void __print(char x) { cerr << '\'' << x << '\''; }
void __print(const char *x) { cerr << '\"' << x << '\"'; }
void __print(const string &x) { cerr << '\"' << x << '\"'; }
void __print(bool x) { cerr << (x ? "true" : "false"); }
 
template <typename T, typename V>
void __print(const pair<T, V> &x)
{
    cerr << '{';
    __print(x.first);
    cerr << ", ";
    __print(x.second);
    cerr << '}';
}
template <typename T>
void __print(const T &x)
{
    int f = 0;
    cerr << '{';
    for (auto &i : x)
        cerr << (f++ ? ", " : ""), __print(i);
    cerr << "}";
}
void _print() { cerr << "]\n"; }
template <typename T, typename... V>
void _print(T t, V... v)
{
    __print(t);
    if (sizeof...(v)) cerr << ", ";
    _print(v...);
}
#ifdef LOCAL
#define debug(x...)               \
    cerr << "[" << #x << "] = ["; \
    _print(x)
#else
#define debug(x...)
#endif
 
typedef pair<int, int> T;
const int oo = 1e9 + 7;
 
struct TreeMin {
    vector<T> tab;
    int size = 1;
 
    TreeMin(int n, vector<int> &a)
    {
        while (size < n)
            size *= 2;
        tab.assign(2 * size, {oo, oo});
        for (int i = 1; i < (int)a.size(); i++)
            tab[i + size] = {a[i], i};
        for (int i = size - 1; i >= 1; i--)
            tab[i] = min(tab[2 * i], tab[2 * i + 1]);
    }
 
    T query(int l, int r)
    {
        T ans = {oo, oo};
        for (l += size - 1, r += size + 1; r - l > 1; l /= 2, r /= 2) {
            if (!(l & 1)) ans = min(ans, tab[l + 1]);
            if (r & 1) ans = min(ans, tab[r - 1]);
        }
        return ans;
    }
 
    void update(int x)
    {
        x += size;
        tab[x] = {oo, oo};
        while (x) {
            x /= 2;
            tab[x] = min(tab[2 * x], tab[2 * x + 1]);
        }
    }
};
 
struct Tree {
    vector<int> tab, lazy;
    int size = 1;
 
    Tree(int n)
    {
        while (size < n)
            size *= 2;
        tab.assign(2 * size, 0);
        lazy.assign(2 * size, 0);
    }
 
    void update(int x, int lx, int rx, int l, int r, int v)
    {
        if (lx > r || rx < l) return;
        if (lx >= l && rx <= r) {
            tab[x] += v;
            lazy[x] += v;
            return;
        }
        if (lx != rx) push(x);
        int m = (lx + rx) / 2;
        update(2 * x, lx, m, l, r, v);
        update(2 * x + 1, m + 1, rx, l, r, v);
        tab[x] = max(tab[2 * x], tab[2 * x + 1]);
    }
 
    void push(int x)
    {
        if (!lazy[x]) return;
        tab[2 * x] += lazy[x];
        tab[2 * x + 1] += lazy[x];
        lazy[2 * x] += lazy[x];
        lazy[2 * x + 1] += lazy[x];
        lazy[x] = 0;
    }
 
    int find(int x, int lx, int rx)
    {
        if (lx == rx) return lx;
        push(x);
        int m = (lx + rx) / 2;
        if (tab[2 * x] < tab[2 * x + 1]) return find(2 * x + 1, m + 1, rx);
        return find(2 * x, lx, m);
    }
};
 
namespace fastio {
static constexpr int SZ = 1 << 17;
char ibuf[SZ], obuf[SZ];
int pil = 0, pir = 0, por = 0;
 
struct Pre {
    char num[40000];
    constexpr Pre() : num()
    {
        for (int i = 0; i < 10000; i++) {
            int n = i;
            for (int j = 3; j >= 0; j--) {
                num[i * 4 + j] = n % 10 + '0';
                n /= 10;
            }
        }
    }
} constexpr pre;
 
inline void load()
{
    memcpy(ibuf, ibuf + pil, pir - pil);
    pir = pir - pil + fread(ibuf + pir - pil, 1, SZ - pir + pil, stdin);
    pil = 0;
}
inline void flush()
{
    fwrite(obuf, 1, por, stdout);
    por = 0;
}
 
inline void rd(char &c) { c = ibuf[pil++]; }
template <typename T>
inline void rd(T &x)
{
    if (pil + 32 > pir) load();
    char c;
    do
        c = ibuf[pil++];
    while (c < '-');
    x = 0;
    while (c >= '0') {
        x = x * 10 + (c & 15);
        c = ibuf[pil++];
    }
}
inline void rd() {}
template <typename Head, typename... Tail>
inline void rd(Head &head, Tail &...tail)
{
    rd(head);
    rd(tail...);
}
 
struct Dummy {
    Dummy() { atexit(flush); }
} dummy;
 
} // namespace fastio
using fastio::rd;
 
void solve()
{
    int n, d, tt;
    rd(n, d, tt);
    vector<int> prev(n + 1, oo);
    stack<int> s;
    vector<int> t(n + 1);
    for (int i = 1; i <= n; i++)
        rd(t[i]);
    for (int i = 1; i <= n; i++) {
        s.push(i);
        while ((int)s.size() && s.top() - t[s.top()] < i - tt)
            s.pop();
        if ((int)s.size()) prev[i] = s.top();
    }
    debug(prev);
    TreeMin tmin(n + 2, prev);
    Tree tans(n + 1);
    for (int i = 1; i <= n; i++) {
        if (prev[i] <= i) {
            debug(prev[i], i);
            tans.update(1, 0, tans.size - 1, prev[i], i, 1);
        }
    }
    while (d--) {
        int x = tans.find(1, 0, tans.size - 1);
        debug(x);
        bool any = 0;
        while (1) {
            T now = tmin.query(x + 1, n + 1);
            if (now.first > x) break;
            debug(now);
            tans.update(1, 0, tans.size - 1, now.first, now.second, -1);
            tmin.update(now.second);
            prev[now.second] = oo;
            any = 1;
        }
        if (!any) break;
    }
    int ans = 0;
    debug(prev);
    for (int i = 1; i <= n; i++)
        if (prev[i] != oo) ans++;
    cout << ans << "\n";
}
 
int32_t main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    solve();
}

• Subtask 1: 15 / 15
• Subtask 2: 10 / 10
• Subtask 3: 20 / 20
• Subtask 4: 10 / 10
• Subtask 5: 25 / 25
• Subtask 6: 20 / 20