Submission #1094781

#	Time	Username	Problem	Language	Result	Execution time	Memory
1094781		manhlinh1501	Sjeckanje (COCI21_sjeckanje)	C++17	55 / 110	46 ms	860 KiB

Main

#include<bits/stdc++.h>
using namespace std;
using i64 = long long;
const int MAXN = 3e3 + 5;
const i64 oo64 = 1e18 + 5;

struct event {
    int l, r, x;
    event(int l = 0, int r = 0, int x = 0) : l(l), r(r), x(x) {}
};

const int INC = 0;
const int DEC = 1;

int N, Q;
i64 a[MAXN];
event query[MAXN];
i64 dp[MAXN][2];

void solve() {
    memset(dp, -0x3f, sizeof dp);

    dp[0][INC] = dp[0][DEC] = 0;

    dp[1][INC] = dp[1][DEC] = 0;

    for(int i = 2; i <= N; i++) {
        dp[i][INC] = dp[i][DEC] = max(dp[i - 1][INC], dp[i - 1][DEC]);
        if(a[i - 1] < a[i]) {
            dp[i][INC] = max(dp[i][INC], max(dp[i - 1][INC], dp[i - 2][DEC]) + a[i] - a[i - 1]);
        } else if(a[i - 1] > a[i]) {
            dp[i][DEC] = max(dp[i][DEC], max(dp[i - 1][DEC], dp[i - 2][INC]) + a[i - 1] - a[i]);
        }
    }
    cout << max(dp[N][INC], dp[N][DEC]) << "\n";
}

signed main() {
    if(fopen(".inp", "r")) {
        freopen(".inp", "r", stdin);
        freopen(".out", "w", stdout);
    }

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin >> N >> Q;

    for(int i = 1; i <= N; i++) cin >> a[i];

    for(int i = 1; i <= Q; i++) {
        auto &[l, r, x] = query[i];
        cin >> l >> r >> x;
    }

    for(int i = 1; i <= Q; i++) {
        const auto [l, r, x] = query[i];

        for(int j = l; j <= r; j++) a[j] += x;

        solve();
    }
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:40:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   40 |         freopen(".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~
Main.cpp:41:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   41 |         freopen(".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 40 / 40
• Subtask 3: 0 / 55