Question:-  How to find an element in rotated sorted array?

Input 1: array[]={4,5,6,7,8,9,1,2,3}; element=5
Output : position of the element(=5) is 1 (array starts from zero).

Input 2: array[]={1,2,3,4,5,6,7,8,9}; element=7
Output : position of the element(=7) is 6 (array starts from zero). 

The below mentioned code has been compiled in Microsoft Visual Studio 6.0 


#include<stdio.h>
int find_element_position(int *a, int first , int last , int element);
main()
{
	int a[10]={3,4,5,6,7,8,9,1,2};
	int pos;
	int element;
	printf("Give the element\n");
	scanf("%d",&element);
	pos=find_element_position(a,0,8 ,element);
	printf("The smallest element=%d position is %d\n",element , pos);
}

int find_element_position(int *a, int first , int last , int element)
{
	int mid;
	int pos = -1;
	while(first<last-1)
	{
		mid=(first+last)/2;
		if(a[mid]==element)
		{
			first=mid;
			break;
		}
		if(a[first]<a[mid])
		{
			if(element >= a[first] && element < a[mid])
			{
				last = mid-1;
			}
			else
			{
				first = mid;
			}
		}
		else
		{
			if(element >=a[mid] && element <= a[last])
			{
				first = mid;
			}
			else
			{
				last = mid-1;
			}
		}

	}
	if(a[first]==element)
		pos=first;
	if(a[last]==element)
		pos=last;
	return pos;
}


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