Cod sursa(job #837567)

Utilizator symonaScheul Simona symona Data 18 decembrie 2012 09:54:38
Problema Cautare binara Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.99 kb
#include<fstream>
using namespace std;
int n,x[100010];

int cb1(int val)
{
    int st,p,med,last=-1;
    st=1;p=n;
    while(st<=p)
    {
        med=(st+p)/2;
        if(val>=x[med])
        {
            last=med;
            st=med+1;
        }
        else p=med-1;
    }
    return last;
}
int cb3(int val)
{
    int st,p,med,last=-1;
    st=1;p=n;
    while(st<=p)
    {
        med=(st+p)/2;
        if(val<=x[med])
        {
            last=med;
            p=med-1;
        }
        else st=med+1;
    }
    return last;
}

int main()
{
    ifstream f("cautbin.in");
    ofstream g("cautbin.out");
    int m,a,b,i,poz;
    f>>n;
    for(i=1;i<=n;i++) f>>x[i];
    f>>m;
    for(i=1;i<=m;i++)
    {
        f>>a>>b;
        poz=cb1(b);
        if(a==0)
            if (x[poz]==b) g<<poz<<'\n';
            else g<<-1<<'\n';
        else if(a==1) g<<poz<<'\n';
        else g<<cb3(b)<<'\n';
    }
    f.close();
    g.close();
    return 0;
}