Cod sursa(job #2289176)

Utilizator Eusebiu_VolostiucVolostiuc Eusebiu Eusebiu_Volostiuc Data 24 noiembrie 2018 11:47:02
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.46 kb
#include <bits/stdc++.h>
#define Nmax 100005
using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");
int v[Nmax], a[4*Nmax],n,m;
int poz;
int start, stop;
inline void build(int l, int r, int node)
{
    if(l==r)
        a[node]=v[l];
    else
    {
        int mid=(l+r)/2;
        build(l,mid, 2*node);
        build(mid+1, r, 2*node+1);

        a[node]=max(a[2*node],a[2*node+1]);
    }
}

inline void update(int l, int r, int node)
{
    if(l==r)
        a[node]=v[l];
    else
    {
        int mid=(l+r)/2;
        if(poz<=mid)
            update(l, mid, 2*node);
        else
            update(mid+1, r, 2*node+1);
        a[node]=max(a[2*node], a[2*node+1]);
    }
}

inline int query(int l, int r, int node)
{
    if(start<=l and stop>=r)
        return a[node];
    else
    {
        int mid=(l+r)/2;
        int maxl=INT_MIN, maxr=INT_MIN;
        if(start<=mid) maxl=query(l, mid, 2*node);
        if(mid+1<=stop) maxr=query(mid+1, r, 2*node+1);
        return max(maxl, maxr);
    }
}

int main()
{
    int op, x, y;
    f>>n>>m;
    for( int i=1; i<=n; i++)
        f>>v[i];
    build(1,n,1);
    for(int i=1; i<=m; i++)
    {
        f>>op>>x>>y;
        if(op==0)
        {
            start=x;
            stop=y;
            g<<query(1,n,1)<<'\n';
        }
        else
        {
            v[x]=y;
            poz=x;
            update(1,n,1);
        }
    }
    return 0;
}