Farey Sequence Time Limit: 1000MS Memory Limit: 65536K Description The Farey Sequence Fn for any integer n with n >= 2 is the set of irreducible rational numbers a/b with 0 < a < b <= n and gcd(a,b) = 1 arranged in increasing order. Th…
hdu1787,直接求欧拉函数 #include <iostream> #include <cstdio> using namespace std; int n; int phi(int n){ int ans=n; for(int i=2; i*i<=n; i++) if(n%i==0){ ans -= ans / i; while(n%i==0) n /= i; } if(n>1) ans -= ans / n; return ans; } int main(){…
题目链接:https://vjudge.net/problem/POJ-2478 Farey Sequence Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 17753 Accepted: 7112 Description The Farey Sequence Fn for any integer n with n >= 2 is the set of irreducible rational numbers a/b…
A - Farey Sequence Time Limit:1000MS Memory Limit:65536KB 64bit IO Format:%I64d & %I64u Submit Status Practice POJ 2478 Description The Farey Sequence Fn for any integer n with n >= 2 is the set of irreducible rational numbers a/b with 0 &l…
题目链接:http://poj.org/problem?id=2478 Description The Farey Sequence Fn for any integer n with n >= 2 is the set of irreducible rational numbers a/b with 0 < a < b <= n and gcd(a,b) = 1 arranged in increasing order. The first few are F2 = {1/2}…
Farey Sequence Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 14291 Accepted: 5647 Description The Farey Sequence Fn for any integer n with n >= 2 is the set of irreducible rational numbers a/b with 0 < a < b <= n and gcd(a,b)…