Submission #960442

#	Time	Username	Problem	Language	Result	Execution time	Memory
960442		AeonARY	Foehn Phenomena (JOI17_foehn_phenomena)	C++17	100 / 100	130 ms	18376 KiB

foehn_phenomena

#include <bits/stdc++.h>
using namespace std;

#define Task "DATA"
#define ll long long
#define int long long
#define pb push_back
#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define FOD(i, a, b) for (int i = (a); i >= (b); i--)

const int N = 1e6 + 6;
const int INF = 1e9;
const int MOD = 1e9 + 7;

int n, q;
ll s, t;
ll a[N], fen[N];

void update(int idx, int val) {
    while (idx < N) {
        fen[idx] += val;
        idx += (idx & -idx);
    }
}

ll get(int idx) {
    ll res = 0;
    while (idx >= 1) {
        res += fen[idx];
        idx -= (idx & -idx);
    }
    return res;
}

ll cost(int x, int y) {
    return (y > x ? -s * (y - x) : t * (x - y));
}

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    if (fopen(Task".INP", "r")) {
        freopen(Task".INP", "r", stdin);
        freopen(Task".OUT", "w", stdout);
    }

    cin >> n >> q >> s >> t;
    FOR(i, 0, n) cin >> a[i];

    ll ans = 0;
    FOR(i, 1, n) {
        update(i, a[i]);
        update(i + 1, -a[i]);
        ans += cost(a[i - 1], a[i]);
    }

    while (q--) {
        int l, r, x;
        cin >> l >> r >> x;

        ans -= cost(get(l - 1), get(l));
        update(l, x);
        ans += cost(get(l - 1), get(l));

        if (r + 1 <= n) {
            ans -= cost(get(r), get(r + 1));
            update(r + 1, -x);
            ans += cost(get(r), get(r + 1));
        }

        cout << ans << "\n";
    }

    return 0;
}

Compilation message (stderr)

foehn_phenomena.cpp: In function 'int32_t main()':
foehn_phenomena.cpp:43:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   43 |         freopen(Task".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foehn_phenomena.cpp:44:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   44 |         freopen(Task".OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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