Submission #903951

# Submission time Handle Problem Language Result Execution time Memory
903951 2024-01-11T15:21:34 Z Flan312 Building Bridges (CEOI17_building) C++17
100 / 100
64 ms 12960 KB
#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define eb emplace_back
#define task ""
#define fast ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
#define nx freopen (task".inp","r",stdin), freopen (task".out","w",stdout);
#define fi first
#define se second
#define pii pair <int, int>
#define tii tuple <int, int, int>
using namespace std;
const int nmax = 1e5 + 2;
const ll oo = 1e18;
int n;
ll h[nmax], w[nmax], dp[nmax];
struct segment
{
    ll a, b;
    segment(ll a = 0, ll b = oo) : a(a), b(b) {}
};
struct node
{
    segment line;
    node *l, *r;
    node(const segment &line = segment(), node *l = nullptr, node *r = nullptr) : line(line), l(l), r(r) {}
};
#define check(x) if (x == nullptr) x = new node()
node *lichao = new node();
ll get(const segment &line, int x)
{
    return line.a * x + line.b;
}
void update(node *root, int l, int r, int u, int v, const segment &line)
{
    if (l > v || r < u) return;
    int mid = l + r >> 1;
    if (l >= u && r <= v)
    {
        check(root -> l);
        check(root -> r);
        ll rootL = get(root -> line, l);
        ll rootR = get(root -> line, r);
        ll rootM = get(root -> line, mid);
        ll lineL = get(line, l);
        ll lineR = get(line, r);
        ll lineM = get(line, mid);
        if (rootL <= lineL && rootR <= lineR) return;
        if (rootL >= lineL && rootR >= lineR) {root -> line = line; return;}
        if (rootL <= lineL && rootM <= lineM)
        {
            update(root -> r, mid + 1, r, u, v, line);
            return;
        }
        if (rootL >= lineL && rootM >= lineM)
        {
            update(root -> r, mid + 1, r, u, v, root -> line);
            root -> line = line;
            return;
        }
        if (get(root -> line, mid + 1) <= get(line, mid + 1) && rootR <= lineR)
        {
            update(root -> l, l, mid, u, v, line);
            return;
        }
        if (get(root -> line, mid + 1) >= get(line, mid + 1) && rootR >= lineR)
        {
            update(root -> l, l, mid, u, v, root -> line);
            root -> line = line;
            return;
        }
    }
    update(root -> l, l, mid, u, v, line);
    update(root -> r, mid + 1, r, u, v, line);
}
void update(int u, int v, const segment &line) {update(lichao, 0, 2e6, 0, 2e6, line);}
ll get(node *root, int l, int r, int x)
{
    if (root == nullptr || (l > x || r < x)) return oo;
    ll res = get(root -> line, x);
    if (l == r) return res;
    int mid = l + r >> 1;
    res = min(res, get(root -> l, l, mid, x));
    res = min(res, get(root -> r, mid + 1, r, x));
    return res;
}
int main()
{
    if (ifstream(task".inp")) nx
    fast
    cin >> n;
    for (int i = 1; i <= n; ++i)
        cin >> h[i];
    for (int i = 1; i <= n; ++i)
        cin >> w[i];;
    dp[1] = -w[1];
    update(1, 2e6, segment(-2 * h[1], 1ll * h[1] * h[1] + dp[1]));
    for (int i = 2; i <= n; ++i)
    {
        dp[i] = 1ll * h[i] * h[i] - w[i] + get(lichao, 0, 2e6, h[i]);
        update(0, 2e6, segment(-2 * h[i], 1ll * h[i] * h[i] + dp[i]));
    }
    cout << dp[n] + accumulate(w + 1, w + n + 1, 0LL);
}

Compilation message

building.cpp: In function 'void update(node*, int, int, int, int, const segment&)':
building.cpp:37:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   37 |     int mid = l + r >> 1;
      |               ~~^~~
building.cpp: In function 'long long int get(node*, int, int, int)':
building.cpp:82:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   82 |     int mid = l + r >> 1;
      |               ~~^~~
building.cpp: In function 'int main()':
building.cpp:7:20: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    7 | #define nx freopen (task".inp","r",stdin), freopen (task".out","w",stdout);
      |            ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
building.cpp:89:31: note: in expansion of macro 'nx'
   89 |     if (ifstream(task".inp")) nx
      |                               ^~
building.cpp:7:52: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    7 | #define nx freopen (task".inp","r",stdin), freopen (task".out","w",stdout);
      |                                            ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
building.cpp:89:31: note: in expansion of macro 'nx'
   89 |     if (ifstream(task".inp")) nx
      |                               ^~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 2400 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 54 ms 4172 KB Output is correct
2 Correct 45 ms 4184 KB Output is correct
3 Correct 47 ms 4112 KB Output is correct
4 Correct 43 ms 3676 KB Output is correct
5 Correct 37 ms 6884 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 2400 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 54 ms 4172 KB Output is correct
7 Correct 45 ms 4184 KB Output is correct
8 Correct 47 ms 4112 KB Output is correct
9 Correct 43 ms 3676 KB Output is correct
10 Correct 37 ms 6884 KB Output is correct
11 Correct 39 ms 4188 KB Output is correct
12 Correct 64 ms 4360 KB Output is correct
13 Correct 37 ms 3872 KB Output is correct
14 Correct 63 ms 4404 KB Output is correct
15 Correct 45 ms 12960 KB Output is correct
16 Correct 41 ms 6884 KB Output is correct
17 Correct 16 ms 3676 KB Output is correct
18 Correct 14 ms 3676 KB Output is correct