【HDU 2824 The Euler function】+ 欧拉函数
2017-03-11 21:08
429 查看
The Euler function
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 6488 Accepted Submission(s): 2736
Problem Description
The Euler function phi is an important kind of function in number theory, (n) represents the amount of the numbers which are smaller than n and coprime to n, and this function has a lot of beautiful characteristics. Here comes a very easy question: suppose you are given a, b, try to calculate (a)+ (a+1)+….+ (b)
Input
There are several test cases. Each line has two integers a, b (2< a < b < 3000000).
Output
Output the result of (a)+ (a+1)+….+ (b)
Sample Input
3 100
Sample Output
3042
Source
2009 Multi-University Training Contest 1 - Host by TJU
题意 : (a) 1 ~ a 中与 a 互质的数的个数,求 (a) + (a + 1) + …(b)
思路 : 欧拉函数求质数~
AC代码:
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 6488 Accepted Submission(s): 2736
Problem Description
The Euler function phi is an important kind of function in number theory, (n) represents the amount of the numbers which are smaller than n and coprime to n, and this function has a lot of beautiful characteristics. Here comes a very easy question: suppose you are given a, b, try to calculate (a)+ (a+1)+….+ (b)
Input
There are several test cases. Each line has two integers a, b (2< a < b < 3000000).
Output
Output the result of (a)+ (a+1)+….+ (b)
Sample Input
3 100
Sample Output
3042
Source
2009 Multi-University Training Contest 1 - Host by TJU
题意 : (a) 1 ~ a 中与 a 互质的数的个数,求 (a) + (a + 1) + …(b)
思路 : 欧拉函数求质数~
AC代码:
#include<cstdio> typedef long long LL; const int K = 3e6 + 10; int ol[K]; int main() { int a,b; for(int i = 1; i < K; i++) ol[i] = i; for(int i = 2; i < K; i++) if(i == ol[i]) // i 为质数 for(int j = i; j < K; j += i) ol[j] = ol[j] / i * (i - 1); // j 的因子有 i,欧拉函数 while(scanf("%d %d",&a,&b) != EOF){ LL cut = 0; for(int i = a; i <= b; i++) cut += ol[i]; printf("%lld\n",cut); } return 0; }
相关文章推荐
- HDU 2824 The Euler function【欧拉函数 打表】
- hdu 2824 The Euler function (欧拉函数离线模板)
- hdu 2824 The Euler function 欧拉函数打表
- hdu 2824 The Euler function(欧拉函数)
- hdu 2824 The Euler function(欧拉函数)
- hdu 2824 The Euler function (欧拉函数)
- HDU-#2824 The Euler function(欧拉函数+筛法)
- 欧拉函数 & 【POJ】2478 Farey Sequence & 【HDU】2824 The Euler function
- HDU:2824 The Euler function(欧拉函数)
- HDU 2824 The Euler function 欧拉函数
- HDU 1787 GCD Again/HDU 2824 The Euler function(欧拉函数模板)
- hdu 2824 The Euler function(欧拉函数)
- HDU 2824 The Euler function【欧拉函数入门题】
- HDU 2824 The Euler function (欧拉函数打表)
- HDU 2824 The Euler function(欧拉函数)
- hdu 2824 The Euler function(欧拉函数)
- HDU 2824(The Euler function)欧拉函数
- hdu 2824 The Euler function 欧拉函数模板题
- HDU 2824 The Euler function(欧拉函数)
- hdu-2824 The Euler function(欧拉函数)