Submission #1302075

#	Time	Username	Problem	Language	Result	Execution time	Memory
1302075		the_commando_x	Foehn Phenomena (JOI17_foehn_phenomena)	C++17	100 / 100	81 ms	9168 KiB

foehn_phenomena

// #pragma GCC optimize("O3")
#include <bits/stdc++.h>

using namespace std;

using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;

using pii = pair<int, int>;
using vii = vector<pii>;
using vvii = vector<vii>;

using l = long long;
using vl = vector<l>;
using vvl = vector<vl>;
using vvvl = vector<vvl>;

using pll = pair<l, l>;
using vll = vector<pll>;
using vvll = vector<vll>;

using d = double;
using vd = vector<d>;
using vvd = vector<vd>;
using vvvd = vector<vvd>;

using ld = long double;
using vld = vector<ld>;
using vvld = vector<vld>;
using vvvld = vector<vvld>;

using vb = vector<bool>;
using vvb = vector<vb>;
using pbb = pair<bool, bool>;
using vbb = vector<pbb>;

#define ff first
#define ss second

#define pb push_back
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) (int)(x).size()

void setIO(string name = "")
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if (!name.empty())
    {
        (void)freopen((name + ".in").c_str(), "r", stdin);
        (void)freopen((name + ".out").c_str(), "w", stdout);
    }
}

const ld pi = 3.14159265358979323846;

const l LINF = 1e18;
const l INF = 1e9;

const l MOD = 1e9 + 7;
// const l MOD = 998244353;

const l MAXN = 2e5 + 5;

struct BIT
{
    l n;
    vl table;

    BIT(l _n = MAXN)
    {
        n = _n;
        table.assign(n + 1, 0);
    }

    BIT(const vl &a) : BIT(a.size())
    {
        n = a.size();

        for (l i = 1; i <= n; ++i)
            table[i] = a[i - 1];

        for (l i = 1; i <= n; ++i)
        {
            l j = i + (i & -i);
            if (j <= n)
                table[j] += table[i];
        }

        // for (int i = 0; i < a.size(); ++i)
        //     update(i + 1, a[i]);
    }

    void update(l i, l delta)
    {
        while (i <= n)
        {
            table[i] += delta;
            i += (i & -i);
        }
    }

    l sum(l i)
    {
        l s = 0;
        while (i != 0)
        {
            s += table[i];
            i -= (i & -i);
        }
        return s;
    }

    l rangeSum(l i, l j)
    {
        return sum(j) - sum(i - 1);
    }
};

l N, Q, S, T;

l cost(l d)
{
    if (d > 0)
        return -S * d;
    return -T * d;
}

void solve()
{
    cin >> N >> Q >> S >> T;

    vl A(N + 1);
    for (int i = 0; i <= N; ++i)
        cin >> A[i];

    vl D(N + 1);
    for (int i = 1; i <= N; ++i)
        D[i] = A[i] - A[i - 1];

    BIT bit(N+1);
    l ans = 0;

    for (int i = 1; i <= N; ++i)
        bit.update(i, D[i]), ans += cost(D[i]);

    while (Q--)
    {
        l L, R, X;
        cin >> L >> R >> X;

        l oldL = bit.rangeSum(L, L);
        ans -= cost(oldL);
        bit.update(L, X);
        ans += cost(oldL + X);

        if (R + 1 <= N)
        {
            l oldR = bit.rangeSum(R + 1, R + 1);
            ans -= cost(oldR);
            bit.update(R + 1, -X);
            ans += cost(oldR - X);
        }

        cout << ans << '\n';
    }
}

int main()
{
    setIO("");

#ifndef ONLINE_JUDGE
    // setIO("filename");
#endif

    int t = 1;
    // cin >> t;
    while (t--)
        solve();

    return 0;
}

Compilation message (stderr)

foehn_phenomena.cpp: In function 'void setIO(std::string)':
foehn_phenomena.cpp:53:22: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   53 |         (void)freopen((name + ".in").c_str(), "r", stdin);
      |               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foehn_phenomena.cpp:54:22: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   54 |         (void)freopen((name + ".out").c_str(), "w", stdout);
      |               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 30 / 30
• Subtask 2: 10 / 10
• Subtask 3: 60 / 60