Submission #781339

#	Time	Username	Problem	Language	Result	Execution time	Memory
781339		makanhulia	Foehn Phenomena (JOI17_foehn_phenomena)	C++17	100 / 100	102 ms	13144 KiB

foehn_phenomena

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long
#define ld long double
#define fi first
#define se second

ll a[200005], diff[200005];

int main() { 
    ios_base::sync_with_stdio(false); cin.tie(NULL);
    int n, q;
    cin >> n >> q;
    ll s, t;
    cin >> s >> t;
    s = -s, t = -t;
    ll ans = 0;
    for (int i = 0; i <= n; i++) cin >> a[i];
    for (int i = 1; i <= n; i++) {
        diff[i] = a[i] - a[i - 1];
        if (diff[i] > 0) ans += s * diff[i];
        else ans += t * diff[i];
    }
    while (q--) {
        int l, r;
        ll x;
        cin >> l >> r >> x;
        if (r == n) {
            if (diff[l] > 0) ans -= s * diff[l];
            else ans -= t * diff[l];
            diff[l] += x;
            if (diff[l] > 0) ans += s * diff[l];
            else ans += t * diff[l];      
            cout << ans << "\n";
            continue;      
        }
        if (diff[l] > 0) ans -= s * diff[l];
        else ans -= t * diff[l];
        if (diff[r + 1] > 0) ans -= s * diff[r + 1];
        else ans -= t * diff[r + 1]; 
        diff[l] += x, diff[r + 1] -= x;
        if (diff[l] > 0) ans += s * diff[l];
        else ans += t * diff[l];
        if (diff[r + 1] > 0) ans += s * diff[r + 1];
        else ans += t * diff[r + 1];
        cout << ans << "\n"; 
    }
} 

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