Cod sursa(job #1180869)

Utilizator bogdan10bosBogdan Sitaru bogdan10bos Data 1 mai 2014 11:44:53
Problema Arbori de intervale Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 1.28 kb
#include <cstdio>
#define lsb(x) (x&(-x))

using namespace std;
int i, n, m, x, y, q, v[100005], a[100005];
inline int minn (int x, int y)
{
    if(x>y) return y;
    return x;
}
inline int maxx (int x, int y)
{
    if(x>y) return x;
    return y;
}
int query(int x, int y)
{
    int i=-1, c=x, b=y;
    if(x>y) return i;
    while(b>=c)
    {
        if(b-lsb(b)>=c)
        {
            i=maxx(i, a[b]);
            b-=lsb(b);
        }
        else
        {
            i=maxx(i, v[b]);
            b--;
        }
    }
    return i;
}
void update(int p, int x)
{
    int y;
    int i=v[p];
    v[p]=x;
    while(p<=n)
    {
        if(a[p]==i)
        {
            y=query(p-lsb(p)+1, p-1);
            a[p]=maxx(v[p], y);
        }
        else
        {
            a[p]=maxx(a[p], x);
            p+=lsb(p);
        }
    }
}
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", &v[i]);
        update(i, v[i]);
    }
    for(i=1;i<=m;i++)
    {
        scanf("%d%d%d", &q, &x, &y);
        if(q==0)
            printf("%d\n", query(x, y));
        else if(v[x]!=y)
            update(x, y);
    }
    return 0;
}