Cod sursa(job #1321092)

Utilizator sasyandreiSasy Ownage sasyandrei Data 18 ianuarie 2015 19:27:14
Problema Cautare binara Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.01 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("cautbin.in");
ofstream fout("cautbin.out");
int N,A[100010],i,j,x,y,l,u,M;
int binary_search(int val)
{
    int i,step;
    for(step=1;step<N;step<<=1);
        for(i=0;step;step>>=1)
            if(i+step<=N && A[i+step]<=val)
                i+=step;
    return i;
}
int binary_search1(int val)
{
    int i,step;
    for(step=1;step<N;step<<=1);
        for(i=0;step;step>>=1)
            if(i+step<=N && A[i+step]<val)
                i+=step;
    return i+1;
}
int main()
{
    fin>>N;
    for(j=0;j<N;j++)
        fin>>A[j];
    fin>>M;
    for(j=0;j<M;j++)
    {
        fin>>x>>y;
        if(x==0)
        {
            l=binary_search(y);
            if(A[l]==y)
                fout<<l+1<<'\n';
            else
                fout<<"-1"<<'\n';
        }
        if(x==1)
            fout<<binary_search1(y+1)-1<<'\n';
        if(x==2)
            fout<<binary_search(y-1)+1<<'\n';
    }
    return 0;
}