def binarySearch(list,b,l,x):
 
    if(l>=b):
        mid = b + (l-b)/2
        mid = int(mid)
        if(list[mid] == x):
            return mid
        elif(list[mid]>x):
            return binarySearch(list,b,mid-1,x)
        elif(list[mid]<x):
            return binarySearch(list,mid+1,l,x)    
 
        return -1   
 
 
if __name__ == "__main__":
    list = [1,2,4,5,7,9,10]
    l = len(list)
    x = 7
 
    answer = binarySearch(list,0,l-1,x)
 
    if (answer == -1) :
        print("Number is not present in the list")
    else:
        print("Number is present at index:", answer )  # your code goes here

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