Cod sursa(job #2718569)

Utilizator NanuGrancea Alexandru Nanu Data 8 martie 2021 20:14:00
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.22 kb
#include <fstream>

using namespace std;

ifstream cin("arbint.in");
ofstream cout("arbint.out");

#define DIM 100001

int arbore[DIM * 4], n, m, i, x, tip, y;

static inline void update(int a, int b, int nod, int poz, int val) {
    if(a == b)
        arbore[nod] = val;
    else {
        int mid = (a + b) / 2;
        if(poz <= mid)
            update(a, mid, nod * 2, poz, val);
        else update(mid + 1, b, nod * 2 + 1, poz, val);
        arbore[nod] = max(arbore[nod * 2], arbore[nod * 2 + 1]);    ///maximul pe fiecare interval
    }
}

static inline int query(int a, int b, int nod, int st, int dr) {
    int max1 = 0, max2 = 0;
    if(st <= a && b <= dr)
        return arbore[nod];
    int mid = (a + b) / 2;
    if(st <= mid)
        max1 = query(a, mid, nod * 2, st, dr);
    if(mid < dr)
        max2 = query(mid + 1, b, nod * 2 + 1, st, dr);
    return max(max1, max2);
}

int main() {
    cin >> n >> m;
    for(i = 1; i <= n; i++) {
        cin >> x;
        update(1, n, 1, i, x);
    }

    for(i = 1; i <= m; i++) {
        cin >> tip >> x >> y;
        if(tip == 0)
            cout << query(1, n, 1, x, y) << '\n';
        else update(1, n, 1, x, y);
    }

    return 0;
}