Cod sursa(job #2032115)

Utilizator LauraNaduLaura Nadu LauraNadu Data 4 octombrie 2017 16:28:52
Problema Cautare binara Scor 80
Compilator cpp Status done
Runda Arhiva educationala Marime 1.54 kb
#include<fstream>
using namespace std;
ifstream f("cautbin.in");
ofstream g("cautbin.out");
int n, m, a[100002], q, x, st, dr, mid;
int main()
{
    f>>n;
    for(int i=1;i<=n;i++)
        f>>a[i];
    f>>m;
    a[0]=-1;a[n+1]=a[n]+1;
    while(m>0)
    {
        f>>q>>x;
        st=1;
        dr=n;
        if(q==0)
        {
            while(st<=dr)
            {
                mid=st+(dr-st)/2;
                if((a[mid]==x)&&(a[mid+1]!=x))
                {
                    g<<mid<<"\n";
                    break;
                }
                else if(a[mid]<=x)
                        st=mid+1;
                     else dr=mid-1;
            }
            if(st>dr)
                g<<"-1\n";
        }
        if(q==1)
        {
            while(st<=dr)
            {
                mid=st+(dr-st)/2;
                if((a[mid]<=x)&&(a[mid+1]>x))
                {
                    g<<mid<<"\n";
                    break;
                }
                else if(a[mid]<=x)
                        st=mid+1;
                     else dr=mid-1;
            }
        }
        if(q==2)
        {
            while(st<=dr)
            {
                mid=st+(dr-st)/2;
                if((a[mid]>=x)&&(a[mid-1]<x))
                {
                    g<<mid<<"\n";
                    break;
                }
                else if(a[mid]<x)
                        st=mid+1;
                     else dr=mid-1;
            }
        }
        m--;
    }
    return 0;
}