Submission #757660

# Submission time Handle Problem Language Result Execution time Memory
757660 2023-06-13T14:14:48 Z maomao90 Tortoise (CEOI21_tortoise) C++17
0 / 100
4 ms 4564 KB
// 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 = 500005;

int n;
int a[MAXN];
int lft[MAXN], rht[MAXN];
int grp[MAXN], lstgrp[MAXN], prvgrp[MAXN];
bool done[MAXN], donewalk[MAXN];
ll ans;

int fw[MAXN];
void fincre(int i, int x) {
    i++;
    for (; i <= n; i += i & -i) {
        fw[i] += x;
    }
}
void fincre(int s, int e, int x) {
    fincre(s, x);
    fincre(e + 1, -x);
}
int fqsm(int i) {
    i++;
    int res = 0;
    for (; i > 0; i -= i & -i) {
        res += fw[i];
    }
    return res;
}

#define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
int st[MAXN * 4], lz[MAXN * 4];
void propo(int u, int lo, int hi) {
    if (lz[u] == 0) {
        return;
    }
    MLR;
    st[lc] += lz[u];
    lz[lc] += lz[u];
    st[rc] += lz[u];
    lz[rc] += lz[u];
    lz[u] = 0;
}
void upd(int p, int x, int u = 1, int lo = 0, int hi = n - 1) {
    if (lo == hi) {
        st[u] = x;
        return;
    }
    MLR;
    propo(u, lo, hi);
    if (p <= mid) {
        upd(p, x, lc, lo, mid);
    } else {
        upd(p, x, rc, mid + 1, hi);
    }
    st[u] = min(st[lc], st[rc]);
}
void incre(int s, int e, int x, int u = 1, int lo = 0, int hi = n - 1) {
    if (s > e) {
        return;
    }
    if (lo >= s && hi <= e) {
        st[u] += x;
        lz[u] += x;
        return;
    }
    MLR;
    propo(u, lo, hi);
    if (s <= mid) {
        incre(s, e, x, lc, lo, mid);
    }
    if (e > mid) {
        incre(s, e, x, rc, mid + 1, hi);
    }
    st[u] = min(st[lc], st[rc]);
}
int qmn(int s, int e, int u = 1, int lo = 0, int hi = n - 1) {
    if (s > e) {
        return INF;
    }
    if (lo >= s && hi <= e) {
        return st[u];
    }
    MLR;
    propo(u, lo, hi);
    int res = INF;
    if (s <= mid) {
        mnto(res, qmn(s, e, lc, lo, mid));
    }
    if (e > mid) {
        mnto(res, qmn(s, e, rc, mid + 1, hi));
    }
    return res;
}

ii st2[MAXN * 4];
int lz2[MAXN * 4];
void propo2(int u, int lo, int hi) {
    if (lz2[u] == 0) {
        return;
    }
    MLR;
    st2[lc].FI += lz2[u];
    lz2[lc] += lz2[u];
    st2[rc].FI += lz2[u];
    lz2[rc] += lz2[u];
    lz2[u] = 0;
}
void upd2(int p, int x, int u = 1, int lo = 0, int hi = n - 1) {
    if (lo == hi) {
        st2[u] = {x, lo};
        return;
    }
    MLR;
    propo2(u, lo, hi);
    if (p <= mid) {
        upd2(p, x, lc, lo, mid);
    } else {
        upd2(p, x, rc, mid + 1, hi);
    }
    st2[u] = min(st2[lc], st2[rc]);
}
void incre2(int s, int e, int x, int u = 1, int lo = 0, int hi = n - 1) {
    if (s > e) {
        return;
    }
    if (lo >= s && hi <= e) {
        st2[u].FI += x;
        lz2[u] += x;
        return;
    }
    MLR;
    propo2(u, lo, hi);
    if (s <= mid) {
        incre2(s, e, x, lc, lo, mid);
    }
    if (e > mid) {
        incre2(s, e, x, rc, mid + 1, hi);
    }
    st2[u] = min(st2[lc], st2[rc]);
}
ii qmn2(int s, int e, int u = 1, int lo = 0, int hi = n - 1) {
    if (s > e) {
        return {INF, INF};
    }
    if (lo >= s && hi <= e) {
        return st2[u];
    }
    MLR;
    propo2(u, lo, hi);
    ii res = {INF, INF};
    if (s <= mid) {
        mnto(res, qmn2(s, e, lc, lo, mid));
    }
    if (e > mid) {
        mnto(res, qmn2(s, e, rc, mid + 1, hi));
    }
    return res;
}

int main() {
#ifndef DEBUG
    ios::sync_with_stdio(0), cin.tie(0);
#endif
    cin >> n;
    ll tot = 0;
    REP (i, 0, n) {
        cin >> a[i];
        if (a[i] > 0) {
            tot += a[i];
        }
    }
    int prv = -INF;
    int gc = 0;
    REP (i, 0, n) {
        if (a[i] == -1) {
            prv = i;
            gc++;
        }
        lft[i] = prv;
        grp[i] = gc;
    }
    prv = INF;
    RREP (i, n - 1, 0) {
        if (a[i] == -1) {
            prv = i;
        }
        rht[i] = prv;
    }
    vi id, pos;
    prv = -1;
    REP (i, 0, n) {
        if (a[i] == -1) {
            lstgrp[grp[i] - 1] = prv;
        }
        if (a[i] <= 0) {
            continue;
        }
        id.pb(i);
        pos.pb(i);
        prv = i;
    }
    sort(ALL(id), [&] (int l, int r) {
            return ii{min(l - lft[l], rht[l] - l), l} < 
            ii{min(r - lft[r], rht[r] - r), r};
            });
    REP (i, 1, n) {
        fincre(i, n - 1, 1);
    }
    REP (i, 0, n) {
        upd(i, INF);
        upd2(i, INF);
    }
    REP (i, 0, gc + 1) {
        if (lstgrp[i] == -1 || grp[lstgrp[i]] != i) {
            continue;
        }
        upd2(lstgrp[i], lstgrp[i]);
    }
    memset(prvgrp, -1, sizeof prvgrp);
    for (int i : id) {
        cerr << i << '\n';
        done[i] = 1;
        int w = 2 * min(i - lft[i], rht[i] - i);
        while (1) {
            // x <= a[i]
            int mn = qmn(i + 1, n - 1);
            assert(mn >= 0);
            // x * w <= mn
            // x <= floor(mn / w)
            int x1 = mn / w;
            int ct = fqsm(i);
            if (ct > 2 * i) {
                break;
            }
            bool delta = 0;
            if (i - lft[i] <= rht[i] - i) { // left cycle
                if (donewalk[grp[i]]) {
                    break;
                }
                auto apply = [&] (int x, bool walk) {
                    if (x + walk == 0) {
                        return;
                    }
                    delta = 1;
                    donewalk[grp[i]] |= walk;
                    cerr << "APPLY: " << x << ' ' << walk << '\n';
                    ans += x + walk;
                    a[i] -= x + walk;
                    fincre(i, n - 1, x * w);
                    incre(i, n - 1, -x * w);
                    incre2(i, n - 1, -x * w);
                    // ct + (x - 1) * w + upd <= 2 * i
                    assert(ct + (x - 1 + walk) * w <= 2 * i);
                    upd(i, 2 * i - (ct + (x - 1 + walk) * w));
                };
                // ct + (x - 1) * w <= 2 * i
                // x <= (2 * i - ct) / w + 1
                int x2 = (2 * i - ct) / w + 1;
                if (a[i] < min(x1, x2)) {
                    auto ptr = upper_bound(ALL(pos), i);
                    bool walk = 0;
                    if (ptr == pos.end() || grp[*ptr] != grp[i] || done[*ptr]) {
                        walk = 1;
                    }
                    if (donewalk[grp[i]]) {
                        walk = 0;
                    }
                    apply(a[i] - walk, walk);
                    if (a[i] + walk) {
                        prvgrp[grp[i]] = i;
                    }
                } else if (rht[i] == INF) {
                    apply(min(x1, x2), 0);
                    if (min(x1, x2)) {
                        prvgrp[grp[i]] = i;
                    }
                } else if (x1 < x2) { // stopped by suffix but still have extra for walk
                    auto ptr = upper_bound(ALL(pos), i);
                    bool walk = 0;
                    if (ptr == pos.end() || grp[*ptr] != grp[i] || done[*ptr]) {
                        walk = 1;
                    }
                    if (donewalk[grp[i]]) {
                        walk = 0;
                    }
                    if (a[i] == x1 && walk) {
                        apply(x1 - 1, 1);
                    } else {
                        apply(x1, walk);
                    }
                } else {
                    // no extra for walk unless replace one cycle with walk
                    int nct = ct + x2 * w;
                    // nct + j - i <= 2 * j
                    // nct - i <= j
                    int j = nct - i;
                    auto ptr = lower_bound(ALL(pos), j);
                    bool walk = 0;
                    if (ptr == pos.end() || grp[*ptr] != grp[i] || done[*ptr]) {
                        walk = 1;
                    }
                    if (donewalk[grp[i]]) {
                        walk = 0;
                    }
                    apply(x2 - walk, walk);
                }
            } else { // right cycle
                auto apply = [&] (int x) {
                    if (x == 0) {
                        return;
                    }
                    delta = 1;
                    cerr << "APPLY: " << x << '\n';
                    a[i] -= x;
                    ans += x;
                    fincre(i, n - 1, x * w);
                    incre(i, n - 1, -x * w);
                    incre2(i, n - 1, -x * w);
                    // ct + x * w + upd <= 2 * i
                    assert(ct + x * w <= 2 * i);
                    upd(i, 2 * i - (ct + x * w));
                };
                auto ptr = lower_bound(ALL(pos), i);
                bool walk = 0;
                if (ptr == pos.begin() || grp[*prev(ptr)] != grp[i] || 
                        done[*prev(ptr)] || fqsm(*prev(ptr)) > 2 * (*prev(ptr))) {
                    walk = 1;
                }
                if (donewalk[grp[i]]) {
                    walk = 0;
                }
                if (walk) {
                    cerr << "WALK\n";
                    donewalk[grp[i]] = 1;
                    a[i]--;
                    ans++;
                    // ct + upd <= 2 * i
                    upd(i, 2 * i - ct);
                } else if (!donewalk[grp[i]]) {
                    assert(lstgrp[grp[i]] == i);
                    upd2(i, INF);
                    lstgrp[grp[i]] = *prev(ptr);
                    int ct = fqsm(*prev(ptr));
                    upd2(*prev(ptr), 2 * (*prev(ptr)) - ct);
                }
                // ct + x * w <= 2 * i
                // x <= (2 * i - ct) / w
                int x2 = (2 * i - ct) / w;
                apply(min({a[i], x1, x2}));
            }
            while (st2[1].FI < 0) {
                int u = st2[1].SE, g = grp[u], v = prvgrp[g];
                upd2(u, INF);
                if (donewalk[g]) {
                    continue;
                }
                cerr << "HI " << u << ' ' << g << ' ' << v << '\n';
                if (v == -1) {
                    continue;
                }
                donewalk[g] = 1;
                int w = 2 * min(v - lft[v], rht[v] - v);
                if (v - lft[v] <= rht[v] - v) {
                    fincre(v + 1, n - 1, -w);
                    incre(v + 1, n - 1, w);
                    incre2(v + 1, n - 1, w);
                } else {
                    fincre(v, n - 1, -w);
                    incre(v, n - 1, w);
                    incre2(v, n - 1, w);
                }
            }
            if (delta) {
                prvgrp[grp[i]] = i;
            } else {
                break;
            }
        }
    }
    cout << tot - ans << '\n';
    return 0;
}

Compilation message

tortoise.cpp: In function 'void propo(int, int, int)':
tortoise.cpp:64:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   64 | #define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
      |                       ~~~^~~~
tortoise.cpp:70:5: note: in expansion of macro 'MLR'
   70 |     MLR;
      |     ^~~
tortoise.cpp:64:17: warning: unused variable 'mid' [-Wunused-variable]
   64 | #define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
      |                 ^~~
tortoise.cpp:70:5: note: in expansion of macro 'MLR'
   70 |     MLR;
      |     ^~~
tortoise.cpp: In function 'void upd(int, int, int, int, int)':
tortoise.cpp:64:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   64 | #define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
      |                       ~~~^~~~
tortoise.cpp:82:5: note: in expansion of macro 'MLR'
   82 |     MLR;
      |     ^~~
tortoise.cpp: In function 'void incre(int, int, int, int, int, int)':
tortoise.cpp:64:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   64 | #define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
      |                       ~~~^~~~
tortoise.cpp:100:5: note: in expansion of macro 'MLR'
  100 |     MLR;
      |     ^~~
tortoise.cpp: In function 'int qmn(int, int, int, int, int)':
tortoise.cpp:64:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   64 | #define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
      |                       ~~~^~~~
tortoise.cpp:117:5: note: in expansion of macro 'MLR'
  117 |     MLR;
      |     ^~~
tortoise.cpp: In function 'void propo2(int, int, int)':
tortoise.cpp:64:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   64 | #define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
      |                       ~~~^~~~
tortoise.cpp:135:5: note: in expansion of macro 'MLR'
  135 |     MLR;
      |     ^~~
tortoise.cpp:64:17: warning: unused variable 'mid' [-Wunused-variable]
   64 | #define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
      |                 ^~~
tortoise.cpp:135:5: note: in expansion of macro 'MLR'
  135 |     MLR;
      |     ^~~
tortoise.cpp: In function 'void upd2(int, int, int, int, int)':
tortoise.cpp:64:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   64 | #define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
      |                       ~~~^~~~
tortoise.cpp:147:5: note: in expansion of macro 'MLR'
  147 |     MLR;
      |     ^~~
tortoise.cpp: In function 'void incre2(int, int, int, int, int, int)':
tortoise.cpp:64:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   64 | #define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
      |                       ~~~^~~~
tortoise.cpp:165:5: note: in expansion of macro 'MLR'
  165 |     MLR;
      |     ^~~
tortoise.cpp: In function 'ii qmn2(int, int, int, int, int)':
tortoise.cpp:64:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   64 | #define MLR int mid = lo + hi >> 1, lc = u << 1, rc = u << 1 ^ 1
      |                       ~~~^~~~
tortoise.cpp:182:5: note: in expansion of macro 'MLR'
  182 |     MLR;
      |     ^~~
# Verdict Execution time Memory Grader output
1 Runtime error 4 ms 4564 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 4 ms 4564 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 4 ms 4564 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 4 ms 4564 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 4 ms 4564 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -