binary_search.py

# helpful logging statements

def binary_search(list,target):
    lower_limit = 0;
    upper_limit = len(list) - 1
	
    while(lower_limit <= upper_limit):
        midpoint = (lower_limit + upper_limit) // 2 
	    midpoint_guess = list[midpoint]
	    print("Guess:", midpoint_guess,"\n")
		
	if(midpoint_guess == target):
	    print("found it")
	    return midpoint
	elif(midpoint_guess > target):
	    upper_limit = midpoint - 1 
	    print(midpoint_guess," was too big. upper_limit is now at", list[upper_limit],"\n")
	elif(midpoint_guess < target):
	    lower_limit = midpoint + 1 
	    print(midpoint_guess, "guess was too small. lower_limit is now at", list[lower_limit])
	else:
	    return None