Cod sursa(job #2274746)

Utilizator FunnyStockyMihnea Andreescu FunnyStocky Data 2 noiembrie 2018 14:07:30
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.1 kb
#include <fstream>

using namespace std;

ifstream fin("arbint.in");
ofstream fout("arbint.out");

const int N=100000+5;

int n,q;
int a[3*N];

inline void upd(int nod,int id,int value,int st,int dr)
{
    if(id<st || dr<id)
    {
        return;
    }
    if(st==dr)
    {
        a[nod]=value;
        return;
    }
    int med=(st+dr)/2;
    upd(2*nod,id,value,st,med);
    upd(2*nod+1,id,value,med+1,dr);
    a[nod]=max(a[2*nod],a[2*nod+1]);
}

inline int ask(int nod,int aa,int b,int st,int dr)
{
    if(dr<aa || b<st)
    {
        return -(1<<30);
    }
    if(aa<=st && dr<=b)
    {
        return a[nod];
    }
    int med=(st+dr)/2;
    return max(ask(2*nod,aa,b,st,med),ask(2*nod+1,aa,b,med+1,dr));
}

int main()
{
    fin>>n>>q;
    for(int i=1;i<=n;i++)
    {
        int x;
        fin>>x;
        upd(1,i,x,1,n);
    }
    while(q--)
    {
        int t,a,b;
        fin>>t>>a>>b;
        if(t==0)
        {
            fout<<ask(1,a,b,1,n)<<"\n";
        }
        else
        {
            upd(1,a,b,1,n);
        }
    }
    return 0;
}