今天刷题刷了这么一道题,
The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. Find the sum of all the primes below two million.
大概意思是10以内的质数加法和为 2 + 3 + 5 + 7 = 17,接着求2000000以内质数加法的和。
分析:要求2000000内质数的和,首先得把...
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其他好文 时间:
2015-07-11 09:18:17
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137
题意:给一个数n,返回小于n的素数个数。思路: 1 class Solution { 2 public: 3 int countPrimes(int n) { 4 bool* isPrime =new bool[n] ; 5 6 memset...
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其他好文 时间:
2015-06-26 22:19:55
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123
#198 House Robber
You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from robbing each of them...
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其他好文 时间:
2015-06-25 21:16:15
阅读次数:
110
Description:Count the number of prime numbers less than a non-negative number,n.题目大意:给一个int,返回小于它的质数的数量。解题思路:打表。public class Solution { public ...
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其他好文 时间:
2015-06-25 11:55:16
阅读次数:
93
Quadratic primes
Problem 27
Euler discovered the remarkable quadratic formula:
n² + n + 41
It turns out that the formula will produce 40 primes for the consecutive values n = 0 to 39. Howe...
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编程语言 时间:
2015-06-17 21:37:46
阅读次数:
149
The prime 41, can be written as the sum of six consecutive primes:
41 = 2 + 3 + 5 + 7 + 11 + 13
This is the longest sum of consecutive primes that adds to a prime below one-hundred.
The longest s...
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其他好文 时间:
2015-06-07 17:35:13
阅读次数:
129
The first two consecutive numbers to have two distinct prime factors are:
14 = 2 × 7
15 = 3 × 5
The first three consecutive numbers to have three distinct prime factors are:
644 = 2² × 7 × 23
...
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其他好文 时间:
2015-06-07 11:08:41
阅读次数:
106
本文是在学习中的总结,欢迎转载但请注明出处:http://blog.csdn.net/pistolove/article/details/46366207
Description:
Count the number of prime numbers less than a non-negative number, n.
思路:
(1)题意为给定整数n,求解n以内的整数中有多少个素数(质数)。
(2)该题涉及到数学相关的知识。首先,看下素数的定义:质数(prime...
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其他好文 时间:
2015-06-04 22:51:54
阅读次数:
142
又水,素数只能是连续的,而且最多才10000! 1 #include 2 3 using namespace std; 4 5 int a[10001]; 6 7 bool is_prime(int x) 8 { 9 if(x == 1) return 0;10 for...
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其他好文 时间:
2015-06-02 21:25:09
阅读次数:
122
Euler discovered the remarkable quadratic formula:
n² + n + 41
It turns out that the formula will produce 40 primes for the consecutive values n = 0 to 39. However, when n = 40, 402 + 40 + 41 = 40...
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其他好文 时间:
2015-06-02 11:16:49
阅读次数:
139