Cod sursa(job #1266475)

Utilizator AlexNiuclaeNiculae Alexandru Vlad AlexNiuclae Data 18 noiembrie 2014 19:47:06
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.17 kb
#include <cstdio>
#include <algorithm>
#define left 2*nod
#define right 2*nod+1

using namespace std;

int n,m,x,poz,op,a,b;
int arb[1<<19];

void update(int nod,int st,int dr)
{
    int mij;

    if (st>=dr) arb[nod]=x;
    else
    {
        mij=(st+dr)>>1;
        if (poz<=mij) update(left,st,mij);
        else update(right,mij+1,dr);

        if (arb[left]>arb[right]) arb[nod]=arb[left];
        else arb[nod]=arb[right];
    }
}

int maxim(int nod,int st,int dr)
{
    int val1=0,val2=0,mij;

    if (a<=st && dr<=b) return arb[nod];

    mij=(st+dr)>>1;
    if (a<=mij) val1=maxim(2*nod,st,mij);
    if (b>mij) val2=maxim(2*nod+1,mij+1,dr);

    return max(val1,val2);
}

int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);

    scanf("%d %d", &n, &m);
    for (poz=1; poz<=n; ++poz)
    {
        scanf("%d", &x);
        update(1,1,n);
    }

    for (; m; --m)
    {
        scanf("%d %d %d", &op, &a, &b);
        if (!op)
            printf("%d\n", maxim(1,1,n));
        else
        {
            poz=a;
            x=b;
            update(1,1,n);
        }
    }

    return 0;
}