Cod sursa(job #1316665)

Utilizator Vele_GeorgeVele George Vele_George Data 13 ianuarie 2015 23:23:28
Problema Arbori de intervale Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.32 kb
#include <iostream>
#include <fstream>
#define nmax 100000
#define inf (1<<30)
using namespace std;

ifstream f("arbint.in");
ofstream g("arbint.out");


int T[4*nmax]; // interval tree

int sol;

void update(int i,int st, int dr, int p, int val) // indicele nodului pe care ne aflam ,intervalul nodului, p-pozitia care vrem sa o modificam cu val
{
    if (st==dr) T[i]=val;
    else
    {
        int mid=(st+dr)/2;
        if (mid < p) update(2*i+1,mid+1, dr, p, val); //dreapta
                else update(2*i, st , mid, p, val); // stanga
        T[i]=max(T[2*i], T[2*i+1]);
    }
}

void search(int i, int st, int dr, int a, int b)
{
    if (a<=st && dr<=b) sol=max(sol, T[i]);
    else
    {
        int mid=(st+dr)/2;
        if (a<=mid) search(2*i, st, mid, a, b);
        if (mid< b) search(2*i+1, mid+1, dr, a, b);
    }
}



int main()
{

    int n,m,x,y,act;
    f>>n>>m;

    for(int i=1; i<=4*nmax; i++)
    {
        T[i]=0;
    }



    for(int i=1; i<=n; i++)
    {
        f>>x;
        update(1,1,n,i,x);
    }

    g<<"err";
    for(int k=1; k<=m; k++)
    {
        f>>act>>x>>y;
        if(act==0)
        {
            sol=0;
            search(1,1,n,x,y);
           // g << sol << " \n " ;
        }
        else update(1,1,n,x,y);
    }


    return 0;
}