Cod sursa(job #728363)

Utilizator a96tudorAvram Tudor a96tudor Data 28 martie 2012 17:56:36
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.21 kb
#include<cstdio>
#define inf 2000000000
#include<algorithm>
using namespace std;
int T[400010],a[100010],tip,x,y,sol,n,m,i;
void update(int nod,int st,int dr,int poz,int val)
{
    if (st==dr) { T[nod]=val;
                  return;
                    }
    int mij=(st+dr)/2;
    if (poz<=mij) update(nod*2,st,mij,poz,val);
            else update(nod*2+1,mij+1,dr,poz,val);
    T[nod]=max(T[nod*2],T[nod*2+1]);
}
int qwery(int nod,int st,int dr,int x,int y)
{
    if (x<=st && dr<=y) return T[nod];
    int mij=(st+dr)/2;
    int sol=-inf;
    if (x<=mij) sol=max(sol,qwery(nod*2,st,mij,x,y));
    if (mij<y) sol=max(sol,qwery(nod*2+1,mij+1,dr,x,y));
    return sol;
}
int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d%d",&n,&m);
    for (i=1;i<=n;i++)
    {
        scanf("%d",&a[i]);
        update(1,1,n,i,a[i]);
    }
    for (i=1;i<=m;i++)
    {
        scanf("%d%d%d",&tip,&x,&y);
        if (tip==0)  {
                        sol=qwery(1,1,n,x,y);
                        printf("%d\n",sol);
                     }
            else { a[x]=y;
                   update(1,1,n,x,a[x]);
                    }
    }
    return 0;
}