Submission #794996

#	Time	Username	Problem	Language	Result	Execution time	Memory
794996		hafo	Sjeckanje (COCI21_sjeckanje)	C++14	110 / 110	521 ms	23164 KiB

Main

#include <bits/stdc++.h>
#define ll long long
#define ull unsigned ll
#define pb push_back
#define pa pair<int, int>
#define pall pair<ll, int>
#define fi first
#define se second
#define TASK "test"
#define Size(x) (int) x.size()
#define all(x) x.begin(), x.end()
using namespace std;

template<typename T1, typename T2> bool mini (T1 &a, T2 b) {if(a > b) a = b; else return 0; return 1;}
template<typename T1, typename T2> bool maxi (T1 &a, T2 b) {if(a < b) a = b; else return 0; return 1;}

const int MOD = 1e9 + 7;
const int LOG = 20;
const int maxn = 2e5 + 7;
const ll oo = 1e18 + 69;

int n, q, l, r, x, d[maxn];
ll a[maxn];

struct ST {
    struct node {
        ll sum[2][2];
    };

    node st[4 * maxn];

    void merge(int id, int l, int r) {
        int mid = l + r >> 1, id1 = (id << 1), id2 = (id << 1 | 1);

        bool ex = 0;
        if((d[mid] < 0 && d[mid + 1] > 0) || (d[mid] > 0 && d[mid + 1] < 0)) ex = 1;
        memset(st[id].sum, 0, sizeof st[id].sum);
        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++) {
                        if(ex == 1 && b != c) continue;
                        maxi(st[id].sum[a][d], st[id1].sum[a][b] + st[id2].sum[c][d]); 
                    }
                }
            }
        }
    }

    void build(int id, int l, int r) {
        if(l == r) {
            st[id].sum[0][1] = abs(d[l]);
            st[id].sum[0][0] = 0;
            st[id].sum[1][0] = 0;
            st[id].sum[1][1] = 0;
            return;
        }
        int mid = l + r >> 1;
        build(id << 1, l, mid);
        build(id << 1 | 1, mid + 1, r);
        merge(id, l, r);
    }

    void update(int id, int l, int r, int pos) {
        if(pos < l || pos > r) return;
        if(l == r) {
            st[id].sum[0][1] = abs(d[l]);
            st[id].sum[0][0] = 0;
            st[id].sum[1][0] = 0;
            st[id].sum[1][1] = 0;
            return;
        }
        int mid = l + r >> 1;
        update(id << 1, l, mid, pos);
        update(id << 1 | 1, mid + 1, r, pos);
        merge(id, l, r);
    }

} st;

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

    //freopen(TASK".inp", "r", stdin);
    //freopen(TASK".out", "w", stdout);

    cin>>n>>q;
    for(int i = 1; i <= n; i++) cin>>a[i];
    for(int i = 1; i <= n; i++) d[i] = (i == n ? 0:a[i] - a[i + 1]);

    st.build(1, 1, n);
    while(q--) {
        cin>>l>>r>>x;
        if(l - 1 >= 1) {
            d[l - 1] -= x;
            st.update(1, 1, n, l - 1);
        } 
        if(r != n) {
            d[r] += x;
            st.update(1, 1, n, r);
        }
        
        ll ans = 0;
        for(int i = 0; i < 2; i++) 
            for(int j = 0; j < 2; j++) maxi(ans, st.st[1].sum[i][j]);
        cout<<ans<<"\n";
    }
    return 0;
}

Compilation message (stderr)

Main.cpp: In member function 'void ST::merge(int, int, int)':
Main.cpp:33:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   33 |         int mid = l + r >> 1, id1 = (id << 1), id2 = (id << 1 | 1);
      |                   ~~^~~
Main.cpp: In member function 'void ST::build(int, int, int)':
Main.cpp:58:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   58 |         int mid = l + r >> 1;
      |                   ~~^~~
Main.cpp: In member function 'void ST::update(int, int, int, int)':
Main.cpp:73:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   73 |         int mid = l + r >> 1;
      |                   ~~^~~

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