Cod sursa(job #1411510)

Utilizator mist.moonDenisa Gherghel mist.moon Data 31 martie 2015 19:10:31
Problema Cautare binara Scor 80
Compilator cpp Status done
Runda Arhiva educationala Marime 1.53 kb
#include <iostream>
#include <stdio.h>
using namespace std;
int n,m,a[100001];

int cautbin0(int x, int p, int q)
{
   while(p<=q)
   {
       int m=p+(q-p)/2;
       if(a[m]==x)
            if(a[m+1]!=x) return m;
            else p=m+1;
       else
            if(a[m]<x) p=m+1;
            else q=m-1;
   }
   return -1;
}

int cautbin1(int x, int p, int q)
{
    while(p<=q)
    {
        int m=p+(q-p)/2;
        if(x==a[m])
            if(a[m+1]!=x) return m;
            else p=m+1;
        else
            if(a[m]<x)
                if(a[m+1]>x) return m;
                else p=m+1;
            else
                if(a[m-1]<x) return m-1;
                else q=m-1;
    }
}

int cautbin2 (int x, int p, int q)
{
    while(p<=q)
    {
        int m=p+(q-p)/2;
        if(x==a[m])
            if(a[m-1]!=x) return m;
            else q=m-1;
        else
            if(a[m]<x)
                if(a[m+1]>x) return m+1;
                else p=m+1;
            else
                if(a[m-1]<x) return m;
                else q=m-1;
    }

}

int main()
{
    freopen("cautbin.in","r",stdin);
    freopen("cautbin.out","w",stdout);
    scanf("%d", &n);
    for(int i=1;i<=n;i++) scanf("%d", &a[i]);
    scanf("%d", &m);
    int tip,x;
    for(int i=1;i<=m;i++)
    {
        scanf("%d %d", &tip, &x);
        if(tip==0) printf("%d \n", cautbin0(x,1,n));
        if(tip==1) printf("%d \n", cautbin1(x,1,n));
        if(tip==2) printf("%d \n", cautbin2(x,1,n));
    }
    return 0;
}