still_foolish的博客

欧拉函数在数论，对正整数n，欧拉函数是小于等于n的数中与n互质的数的数目。例如φ(8)=4，因为1,3,5,7均和8互质。通式：其中p1, p2……pn为x的所有质因数，x是不为0的整数。 φ(1)=1（唯一和1互质的数(小于等于1)就是1本身）。注意：每种质因数只一个。 比如12=2*2*3那么φ（12）=12*（1-1/2）*(1-1/3)=4 若n是 质数 p的k次幂， ，因为除了p的倍

题目链接 The Euler functionTime Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 5799 Accepted Submission(s): 2455Problem Description The Euler func

链接HDU1286 找新朋友Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 11399 Accepted Submission(s): 6096Problem Description 新年快到了，“猪头帮协会”准备搞一个聚会，已

GCDTime Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 1803 Accepted Submission(s): 901Problem Description The greatest common divisor GCD(a,b)

Stern-Brocot TreeTime Limit: 3000/1000 MS (Java/Others) Memory Limit: 65535/32768 K (Java/Others) Total Submission(s): 582 Accepted Submission(s): 325Problem Description 　　　　 　　上图是一棵Stern-Broc

Interesting FibonacciTime Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 1072 Accepted Submission(s): 230Problem Description In mathematics, th

A/BTime Limit: 1000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 4627 Accepted Submission(s): 3610Problem Description 要求(A/B)%9973，但由于A很大，我们只给出n(n=A%9973

RomanticTime Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 5370 Accepted Submission(s): 2260Problem Description The Sky is Sprite. The Birds

PagodasTime Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 1183 Accepted Submission(s): 841Problem Description n pagodas were standing erect in