Cod sursa(job #1090827)

Utilizator horatiu11Ilie Ovidiu Horatiu horatiu11 Data 23 ianuarie 2014 09:33:58
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.22 kb
//horatiu11
# include <cstdio>
# define nmax 1<<19
using namespace std;
int n,m,x,poz,op,a,b,arb[nmax];
inline void update(int nod, int st, int dr)
{
    int m;
    if(st>=poz && dr<=poz)
    {
        arb[nod]=x;
        return;
    }
    m=(st+dr)>>1;
    if(poz<=m)update(nod<<1,st,m);
    else update((nod<<1)+1,m+1,dr);
    if(arb[nod<<1]<arb[(nod<<1)+1])arb[nod]=arb[(nod<<1)+1];
    else arb[nod]=arb[nod<<1];
}
inline int query(int nod, int st, int dr)
{
    int m,x1=0,x2=0;
    if(a<=st && dr<=b)return arb[nod];
    m=(st+dr)>>1;
    if(a<=m)x1=query(nod<<1,st,m);
    if(b>m) x2=query((nod<<1)+1,m+1,dr);
    if(x2>x1)return x2;
    else return x1;
}
int main()
{
    int i;
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(i=1;i<=n;++i)
    {
        scanf("%d",&x);
        poz=i;
        update(1,1,n);
    }
    for(i=1;i<=m;++i)
    {
        scanf("%d%d%d",&op,&a,&b);
        switch(op)
        {
            case 0:
                printf("%d\n",query(1,1,n));
                break;
            case 1:
                poz=a;x=b;
                update(1,1,n);
                break;
        }
    }
    return 0;
}