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Power digit sum $2^{15} = 32768$ and the sum of its digits is $3 + 2 + 7 + 6 + 8 = 26$. What is the sum of the digits of the number $2^{1000}$? 幂的数字和 阅读全文
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Lattice paths Starting in the top left corner of a 2×2 grid, and only being able to move to the right and down, there are exactly 6 routes to the bott 阅读全文
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Longest Collatz sequence The following iterative sequence is defined for the set of positive integers: n → n/2 (n is even) n → 3n + 1 (n is odd) Using 阅读全文
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Large sum Work out the first ten digits of the sum of the following one hundred 50 digit numbers. 大和 计算出以下一百个50位数的和的前十位数字。 解题思路 目前想到的就是用高精度加法模拟。 100个5 阅读全文
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题目链接： "https://www.luogu.com.cn/problem/P1016" 解题思路（思路全部来自 "hongzy大神的博客" ）： 思路： 1. 在起点加满油； 2. 到第i个加油站把油箱里价格 P[i]的油退了，换成价格为P[i]的油。 3. 每次烧油就找最便宜的油烧 实现:单 阅读全文