"C-Language Program" Valeo series

For any given natural number N, the irreducible true fraction of the denominator less than or equal to n is arranged in ascending order, and the first score is preceded by 0/1, followed by the last score plus 1/1, which is known as the N-level sequence of mines, denoted by FN. such as F5:0/1,1/5, 1/4, 1/3, 2/5, 1/2, 3/5, 2/3, 3/4, 4/5,1/1. The number of elements is 11.

Now give n lets you ask for the permutation and number of elements in the N-level sequence of lightning.

1#include <stdio.h>2#include <stdlib.h>3 intn,s;4 voidPreintAintBintCintD) {//using binary method to output the sequence of thunder5     if(b+d>n)return ;6Pre (a,b,a+c,b+d);7printf"%d/%d,", a+c,b+d);8Pre (a+c,b+d,c,d);9 }Ten     intEular (intN) {//using Euler function to find the number of N-Reciprocity One     Doublesum=N; A     inti; -      for(i=2; i<=n;i++){ -         if(n%i==0){ theSum*= (1-1.0/i); -              while(n%i==0){     -n=n/i; -             } +         } -     } +     return(int) sum; A } at intSUM (intN//Euler function Summation - { -     intj,sum=0; -      for(j=2; j<=n;j++) -sum+=Eular (j); - returnsum; in } -  to intMain () + {   -scanf"%d",&n); theprintf"0/1,"); *Pre0,1,1,1); $printf"1/1\n");Panax Notoginsengs=SUM (n); -printf"%d", s+2); the        +       return 0; A}

"C-Language Program" Valeo series