Submission #386326

#	Time	Username	Problem	Language	Result	Execution time	Memory
386326		phathnv	Sjeckanje (COCI21_sjeckanje)	C++11	55 / 110	48 ms	748 KiB

Main

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

typedef long long ll;

const int N = 3007;

int n, q, a[N];
ll b[N], dp[N][2];

int getSign(ll x){
    if (x < 0)
        return -1;
    else if (x == 0)
        return 0;
    else
        return 1;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    cin >> n >> q;
    if (max(n, q) > 3000)
        return 0;

    for(int i = 1; i <= n; i++)
        cin >> a[i];
    for(int i = 1; i < n; i++)
        b[i] = a[i + 1] - a[i];

    while (q--){
        int l, r, x;
        cin >> l >> r >> x;
        if (l > 1)
            b[l - 1] += x;
        if (r < n)
            b[r] -= x;
//        cerr << "b: ";
//        for(int i = 1; i < n; i++)
//            cerr << b[i] << ' ';
//        cerr << endl;
        dp[0][0] = dp[0][1] = 0;
        for(int i = 1; i < n; i++){
            dp[i][0] = max(dp[i - 1][0], dp[i - 1][1]);
            dp[i][1] = dp[i - 1][0] + abs(b[i]);
            if (getSign(b[i - 1]) * getSign(b[i]) != -1)
                dp[i][1] = max(dp[i][1], dp[i - 1][1] + abs(b[i]));
        }
        cout << max(dp[n - 1][0], dp[n - 1][1]) << '\n';
    }

    return 0;
}

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