def binary_search_count(A, val):
    count = 0
    left = 0
    right = len(A) - 1
    while left <= right:
        count = count + 1
        pivot = (left+right) // 2
        if A[pivot] == val:
            print("発見!", count)
            return True
        elif A[pivot] > val:
            right = pivot - 1
        else:
            left = pivot + 1
    print("未発見", count)
    return False

A = [1,2,3,4,5,6,7,8,9,10]
binary_search_count(A, 1)
binary_search_count(A, 7)
binary_search_count(A, 11)
