Cod sursa(job #285277)

Utilizator cotofanaCotofana Cristian cotofana Data 22 martie 2009 14:42:42
Problema Cautare binara Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.14 kb
#include <stdio.h>
#define dim 100100

int n, m, v[dim];

int caut_bin(int x)
{
	int lo=1, hi=n, mid;
	while (lo<=hi)
	{
		mid=lo+(hi-lo)/2;
		if (v[mid]==x) return x;
		if (x<v[mid]) hi=mid-1;
		else lo=mid+1;
	}
	return -1;
}

int main()
{
	int i, op, x, poz;
	freopen("cautbin.in", "r", stdin);
	freopen("cautbin.out", "w", stdout);
	scanf("%d\n", &n);
	for (i=1; i<=n; i++) scanf("%d ", &v[i]);
	scanf("%d\n", &m);
	for (i=1; i<=m; i++)
	{
		scanf("%d %d\n", &op, &x);
		if (op==0)
		{
			poz=caut_bin(x);
			if (poz==-1) printf("-1\n");
			else
			{
				while (v[poz]==x) poz++;
				printf("%d\n", poz-1);
			}
		}
		else if (op==1)
		{
			poz=caut_bin(x);
			if (v[poz]==x) 
			{
				while (v[poz]==x) poz--;
				printf("%d\n", poz);
			}
			else
			{
				while (v[poz]<x) poz++;
				while (v[poz]>x) poz--;
				printf("%d\n", poz);
			}
		}
		else if (op==2)
		{
			poz=caut_bin(x);
			if (v[poz]==x)
			{
				while (v[poz]==x) poz++;
				printf("%d\n", poz);
			}
			else
			{
				while (v[poz]>x) poz--;
				while (v[poz]<x) poz++;
				printf("%d\n", poz);
			}
		}
	}
	return 0;
}