Submission #386329

#	Time	Username	Problem	Language	Result	Execution time	Memory
386329		phathnv	Sjeckanje (COCI21_sjeckanje)	C++11	55 / 110	575 ms	620 KiB

Main

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

typedef long long ll;

const int N = 3007;
const ll INF = 1e18;

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;
}

struct Node{
    ll dp[2][2], leftVal, rightVal;
    Node(int x = 0){
        dp[0][0] = 0;
        dp[1][1] = abs(x);
        dp[0][1] = dp[1][0] = -INF;
        leftVal = rightVal = x;
    }
    void update(ll delta){
        leftVal += delta;
        rightVal += delta;
    }
    Node operator + (const Node &oth){
        Node res;
        res.leftVal = leftVal;
        res.rightVal = oth.rightVal;
        for(int i = 0; i < 2; i++)
            for(int j = 0; j < 2; j++)
                res.dp[i][j] = -INF;
        for(int a = 0; a < 2; a++)
            for(int b = 0; b < 2; b++)
                for(int c = 0; c < 2; c++)
                    for(int d = 0; d < 2; d++){
                        ll val = dp[a][b] + oth.dp[c][d];
                        if (b && c && getSign(rightVal) * getSign(oth.leftVal) == -1)
                            val -= min(abs(rightVal), abs(oth.leftVal));
                        res.dp[a][d] = max(res.dp[a][d], val);
                    }
        return res;
    }
};

struct segmentTree{

};

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;
        Node res(b[1]);
        for(int i = 2; i < n; i++)
            res = res + Node(b[i]);
        cout << max(max(res.dp[0][0], res.dp[0][1]), max(res.dp[1][0], res.dp[1][1])) << '\n';
    }

    return 0;
}

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