Cod sursa(job #1819315)

Utilizator BeilandArnoldArnold Beiland BeilandArnold Data 30 noiembrie 2016 14:59:21
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.1 kb
#include <fstream>
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int n,m;
vector<int> arb;

void update(int st, int dr, int nod, int i, int val){
    if(st==i && dr==i){
            arb[nod]=val;
        return;
    }

    int mij=(st+dr)/2;
    if(i<=mij){
        update(st,mij,2*nod,i,val);
    }
    else{
        update(mij+1,dr,2*nod+1,i,val);
    }
    arb[nod]=max(arb[2*nod],arb[2*nod+1]);
}

int query(int st, int dr, int nod, int a,int b){
    if(a<=st && b>=dr) return arb[nod];

    int mij = (st+dr)/2;
    int mx=0;

    if(a<=mij){
        mx = max(mx,query(st,mij,2*nod,a,b));
    }
    if(b>mij){
        mx = max(mx,query(mij+1,dr,2*nod+1,a,b));
    }

    return mx;
}


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

    fin>>n>>m;
    arb.resize(8*n+5,0);

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


    for(int i=0;i<m;++i){
        int c,a,b;
        fin>>c>>a>>b;
        if(c==0){
            fout<<query(1,n,1,a,b)<<'\n';
        }
        else update(1,n,1,a,b);
    }

    return 0;
}