PerfectSquare-Binary Search.c

 //Program in C to implement binary search algorithm while finding out whether a number is a perfect square or not
 #include<stdio.h>
 
 //Recursive function to implement binary search.It returns the number,of which the given number is a perfect square.
 //Otherwise,it returns the floor of it's square root.(rounded off to the next integer)
 //e.g.,for 100,it will return 10.While for 99,it will also return 10.
 
 int perfectSquare(int l,int r,int number)
 {
 	int mid=(l+r)/2;
 	//Binary Search
 	while(l<=r)
 	{
 		if(l>r)
		 {
 				return -1;
		 } 
 		if(mid*mid==number)
 			return mid;
 		//moves to left half
		else if(mid*mid>number)
 			return perfectSquare(l,mid-1,number);
 		//moves to right half
		 else
 			return perfectSquare(mid+1,r,number);
 		
	}
}
 
 //Driver program to test the above function
 int main()
 {
 	int number=1225;
 	printf("%d",perfectSquare(1,number,number));
	 
	 return 0;
 	
 }