25 lines
806 B
Python
25 lines
806 B
Python
# coding=utf-8
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''' Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:
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1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...
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By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms. '''
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fib = [1, 1, 0] # 设置 fib 数列循环的数组
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i = 1 # fib 数列的项计数器
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total = 0 # 满足条件的数的和
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while fib[i] <= 4000000: # fib 数列小于要求值时不断循环
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if fib[i] % 2 == 0:
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print fib[i]
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total += fib[i] # 满足条件的项计入总和
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i = (i + 1) % 3 # 项计数器
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fib[i] = fib[(i + 1) % 3] + fib[(i + 2) % 3] #
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print total #
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a, b = 2, 8
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total = 0
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while a < 4000000:
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total += a
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a, b = b, a + b * 4
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print total
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