Cod sursa(job #1040230)

Utilizator gabrielinelusGabriel-Robert Inelus gabrielinelus Data 24 noiembrie 2013 11:07:58
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.28 kb
#include <cstdio>
#include <algorithm>

#define Nmax 4 * 100005
#define INF 0x3f3f3f3f;

using namespace std;
int x,st,dr,ind,ans;
int range[ Nmax ];

void Update(int li,int lf,int pz)
{
    if(li == lf)
    {
        range[ pz ] = x;
        return;
    }
    int m = li +((lf-li)>>1);
    if(ind <= m) Update(li,m,pz<<1);
    if(ind > m) Update(m+1,lf,(pz<<1)+1);
    range[ pz ] = max ( range[pz << 1] , range[(pz<<1) + 1]);
}

void Querry(int li,int lf,int pz)
{
    if(st <= li && lf <= dr)
    {
        ans = max(ans,range[ pz ]);
        return;
    }
    int m = li + ((lf-li)>>1);
    if(st <= m) Querry(li,m,pz<<1);
    if(dr > m) Querry(m+1,lf,(pz<<1)+1);
}

int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    int N,M,op;
    scanf("%d%d",&N,&M);
    for(int i = 1; i <= N; ++i)
    {
        ind = i;
        scanf("%d",&x);
        Update(1,N,1);
    }
    for(int i = 1; i <= M; ++i)
    {
        scanf("%d",&op);
        if(op == 0)
        {
            ans = -INF;
            scanf("%d%d",&st,&dr);
            Querry(1,N,1);
            printf("%d\n",ans);
        }
        else
        {
            scanf("%d%d",&ind,&x);
            Update(1,N,1);
        }
    }

    return 0;
}