Submission #63497

#	Time	Username	Problem	Language	Result	Execution time	Memory
63497		qkxwsm	Palembang Bridges (APIO15_bridge)	C++17	63 / 100	2104 ms	263168 KiB

bridge

#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using orderedset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

template<class T>
void readi(T &x)
{
        T input = 0;
        bool negative = false;
        char c = ' ';
        while (c < '-')
        {
                c = getchar();
        }
        if (c == '-')
        {
                negative = true;
                c = getchar();
        }
        while (c >= '0')
        {
                input = input * 10 + (c - '0');
                c = getchar();
        }
        if (negative)
        {
                input = -input;
        }
        x = input;
}
template<class T>
void printi(T output)
{
        if (output == 0)
        {
                putchar('0');
                return;
        }
        if (output < 0)
        {
                putchar('-');
                output = -output;
        }
        int aout[20];
        int ilen = 0;
        while(output)
        {
                aout[ilen] = ((output % 10));
                output /= 10;
                ilen++;
        }
        for (int i = ilen - 1; i >= 0; i--)
        {
                putchar(aout[i] + '0');
        }
        return;
}
template<class T>
void ckmin(T &a, T b)
{
        a = min(a, b);
}
template<class T>
void ckmax(T &a, T b)
{
        a = max(a, b);
}
template<class T, class U>
T normalize(T x, U mod = 1000000007)
{
        return (((x % mod) + mod) % mod);
}
long long randomizell(long long mod)
{
        return ((1ll << 45) * rand() + (1ll << 30) * rand() + (1ll << 15) * rand() + rand()) % mod;
}
int randomize(int mod)
{
        return ((1ll << 15) * rand() + rand()) % mod;
}

#define y0 ___y0
#define y1 ___y1
#define MP make_pair
#define MT make_tuple
#define PB push_back
#define PF push_front
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define debug(x) cerr << #x << " = " << x << endl;

const long double PI = 4.0 * atan(1.0);
const long double EPS = 1e-10;

#define MAGIC 347
#define SINF 10007
#define CO 1000007
#define INF 1000000007
#define BIG 1000000931
#define LARGE 1696969696967ll
#define GIANT 2564008813937411ll
#define LLINF 2696969696969696969ll
#define MAXN 100013

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

int N, K, M;
ll ans = 0, best = LLINF;
vector<pll> ranges;
vector<ll> pos;
vector<pii> upds[MAXN];
ll pref[MAXN];

struct pseg
{
        struct node
        {
                node *ch[2];
                ll stor;
        };
        int T;
        node *root[MAXN];
        int ft[MAXN];
        node* build(int L, int R)
        {
                node *t = new node();
                t -> stor = 0;
                if (L == R)
                {
                        return t;
                }
                int mid = (L + R)/2;
                t -> ch[0] = build(L, mid);
                t -> ch[1] = build(mid + 1, R);
                return t;
        }
        node* update(node* w, int L, int R, int a, int val)
        {
                if (a < L || R < a)
                {
                        return w;
                }
                node *t = new node();
                if (L == R)
                {
                        t -> stor = w -> stor + val;
                        return t;
                }
                int mid = (L + R)/2;
                t -> ch[0] = update(w -> ch[0], L, mid, a, val);
                t -> ch[1] = update(w -> ch[1], mid + 1, R, a, val);
                t -> stor = t -> ch[0] -> stor + t -> ch[1] -> stor;
                return t;
        }
        ll query(node *w, int L, int R, int a, int b)
        {
                if (b < L || R < a)
                {
                        return 0;
                }
                if (a <= L && R <= b)
                {
                        return w -> stor;
                }
                int mid = (L + R)/2;
                return query(w -> ch[0], L, mid, a, b) + query(w -> ch[1], mid + 1, R, a, b);
        }
};

pseg seg[2];

bool cmp(pll a, pll b)
{
        return a.fi + a.se < b.fi + b.se;
}
ll get(int a, int lt, int rt)
{
        ll res = seg[0].query(seg[0].root[seg[0].ft[a + 1]], 0, N, lt, rt);
        return res;
}
ll cget(int a, int lt, int rt)
{
        ll res = seg[1].query(seg[1].root[seg[1].ft[a + 1]], 0, N, lt, rt);
        // cerr << "at time "<< a + 1 << " query " << lt << ' ' << rt << " gives " << res << endl;
        return res;
}
ll f(ll a, ll b)
{
        ll res = 0;
        ll x = pos[a], y = pos[b];
        int lo = 0, hi = N;
        while(hi > lo)
        {
                int mid = (hi + lo) / 2;
                if (ranges[mid].fi + ranges[mid].se >= x + y)
                {
                        hi = mid;
                }
                else
                {
                        lo = mid + 1;
                }
        }
        //at time x, query(0, lo)
        //at time y, query(y, hi)
        ll xl = get(a, 0, lo - 1), xg = pref[lo] - xl;
        ll yl = get(b, lo, N), yg = pref[N] - pref[lo] - yl;
        ll xlc = cget(a, 0, lo - 1), xgc = 2 * lo - xlc;
        ll ylc = cget(b, lo, N), ygc = 2 * N - 2 * lo - ylc;
        res = (xlc * x - xl) + (xg - xgc * x) + (ylc * y - yl) + (yg - ygc * y);
        // cerr << "# of guys with pos < " << lo << " value <= " << x << " is " << xlc << endl;
        // for (int i = 0; i < lo; i++)
        // {
        //         res += abs(x - ranges[i].fi) + abs(x - ranges[i].se);
        // }
        // for (int i = lo; i < N; i++)
        // {
        //         res += abs(y - ranges[i].fi) + abs(y - ranges[i].se);
        // }
        return res;
}

void solve(int L, int R, int optl, int optr)
{
        if (L > R)
        {
                return;
        }
        ll cur = LLINF;
        int mid = (L + R) / 2, opt = -1;
        for (int i = max(mid + 1, optl); i <= optr; i++)
        {
                if (f(mid, i) <= cur)
                {
                        opt = i;
                        cur = f(mid, i);
                }
        }
        ckmin(best, cur);
        solve(L, mid - 1, optl, opt);
        solve(mid + 1, R, opt, optr);
}

int32_t main()
{
        // ios_base::sync_with_stdio(0);
        srand(time(0));
        //	cout << fixed << setprecision(10);
        //	cerr << fixed << setprecision(10);
        if (fopen("input.in", "r"))
        {
                freopen ("input.in", "r", stdin);
                freopen ("output.out", "w", stdout);
        }
        readi(K); readi(N);
        for (int i = 0; i < N; i++)
        {
                char c1; int x; char c2; int y;
                c1 = getchar(); readi(x); c2 = getchar(); readi(y);
                if (c1 == 'B')
                {
                        swap(c1, c2);
                        swap(x, y);
                }
                if (c1 == c2)
                {
                        ans += abs(y - x);
                }
                else
                {
                        ranges.PB({x, y});
                }
        }
        N = ranges.size();
        if (N == 0)
        {
                printi(ans); putchar('\n');
                return 0;
        }
        ans += N;
        pos.reserve(2 * N);
        for (int i = 0; i < N; i++)
        {
                pos.PB(ranges[i].fi);
                pos.PB(ranges[i].se);
        }
        sort(pos.begin(), pos.end());
        if (K == 1 || N == 1)
        {
                for (pll x : ranges)
                {
                        ans += abs(x.fi - pos[pos.size() / 2]);
                        ans += abs(x.se - pos[pos.size() / 2]);
                }
                printi(ans); putchar('\n');
                return 0;
        }
        pos.erase(unique(pos.begin(), pos.end()), pos.end());
        M = pos.size();
        sort(ranges.begin(), ranges.end(), cmp);
        for (int i = 0; i < N; i++)
        {
                pref[i + 1] = pref[i] + ranges[i].fi + ranges[i].se;
        }
        for (int i = 0; i < N; i++)
        {
                int x1 = LB(pos.begin(), pos.end(), ranges[i].fi) - pos.begin();
                int x2 = LB(pos.begin(), pos.end(), ranges[i].se) - pos.begin();
                upds[x1].PB({i, 0});
                upds[x2].PB({i, 1});
                // cerr << "guy " << i << " is " << x1 << "," << x2 << endl;
        }
        seg[0].root[0] = seg[0].build(0, N);
        seg[1].root[0] = seg[1].build(0, N);
        for (int i = 0; i <= M; i++)
        {
                seg[0].ft[i] = seg[0].T;
                seg[1].ft[i] = seg[1].T;
                for (pii p : upds[i])
                {
                        ll val = (p.se ? ranges[p.fi].se : ranges[p.fi].fi);
                        // cerr << "at time " << i << " update " << p.fi << "," << p.se << endl;
                        seg[0].T++;
                        seg[1].T++;
                        seg[0].root[seg[0].T] = seg[0].update(seg[0].root[seg[0].T - 1], 0, N, p.fi, val);
                        seg[1].root[seg[1].T] = seg[1].update(seg[1].root[seg[1].T - 1], 0, N, p.fi, 1);
                }
        }
        solve(0, pos.size() - 2, 1, pos.size() - 1);
        ans += best;
        printi(ans); putchar('\n');
        //	cerr << "time elapsed = " << (clock() / (CLOCKS_PER_SEC / 1000)) << " ms" << endl;
        return 0;
}

Compilation message (stderr)

bridge.cpp: In function 'int32_t main()':
bridge.cpp:263:25: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
                 freopen ("input.in", "r", stdin);
                 ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bridge.cpp:264:25: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
                 freopen ("output.out", "w", stdout);
                 ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 14 / 14
• Subtask 3: 9 / 9
• Subtask 4: 32 / 32
• Subtask 5: 0 / 37