Cod sursa(job #841219)

Utilizator monica11Szekely Monica monica11 Data 23 decembrie 2012 22:04:36
Problema Cautare binara Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.3 kb
#include<fstream>
using namespace std;
int n,a[100001],m,x,y;
int bin_search0( int st, int dr,int x)
{
    int mij;
    while(st<=dr)
    {
        mij=(st+dr)/2;
        if(a[mij]<=x)
            st=mij+1;
        else
            dr=mij-1;
    }
    mij=(st+dr)/2;
    if(a[mij]>x)
        --mij;
    if(a[mij]==x)
        return mij;
    else
        return -1;
}
int bin_search1(int st,int dr,int x)
{
    int mij;
    while(st<dr)
    {
        mij=(st+dr)/2;
        if(a[mij]<=x)
            st=mij+1;
        else
            dr=mij;
    }
    mij=(st+dr)/2;
    if(a[mij]>x)
        --mij;
    return mij;
}
int bin_search2 (int st, int dr, int x)
{
    int mij;
    while(st<dr)
    {
        mij=(st+dr)/2;
        if(a[mij]>=x)
            dr=mij;
        else
            st=mij+1;
    }
    mij=(st+dr)/2;
    if(a[mij]<x)
        ++mij;
    return mij;
}
int main()
{
    ifstream f("cautbin.in");
    ofstream g("cautbin.out");
    f>>n;
    for(int i=1;i<=n;i++)
        f>>a[i];
    f>>m;
    for(int i=1;i<=m;i++)
    {
        f>>y>>x;
        if(y==0)
            g<<bin_search0(1,n,x)<<"\n";
        if(y==1)
            g<<bin_search1(1,n,x)<<"\n";
        if(y==2)
            g<<bin_search2(1,n,x)<<"\n";
    }
    return 0;
}