Fractions Again?!(简单枚举)

来源:互联网 发布:淘宝店铺新开0信誉排名 编辑:程序博客网 时间:2024/05/17 04:59

Fractions Again?!

It is easy to see that for every fraction in the form 1/k (k > 0), we can always find two positive integers x and y, x >= y, such that: 
.
Now our question is: can you write a program that counts how many such pairs of x and y there are for any given k?

Input

Input contains no more than 100 lines, each giving a value of k (0 < k <= 10000).

Output

For each k, output the number of corresponding (x, y) pairs, followed by a sorted list of the values of x and y, as shown in the sample output.

Sample Input

2
12

Sample Output

2
1/2 = 1/6 + 1/3
1/2 = 1/4 + 1/4
8
1/12 = 1/156 + 1/13
1/12 = 1/84 + 1/14
1/12 = 1/60 + 1/15
1/12 = 1/48 + 1/16
1/12 = 1/36 + 1/18
1/12 = 1/30 + 1/20
1/12 = 1/28 + 1/21

1/12 = 1/24 + 1/24


/// 1/n = 1/x + 1/y ==> n*y + n*x = x*y;///y只需要从n+1枚举到2*n即可,此时x = n*y / (y-n);#include<stdio.h>#include<string.h>int main(){    int n,i,p,num;    int a[10000],b[10000];    while(~scanf("%d",&n))    {        memset(a,0,sizeof(a));        memset(b,0,sizeof(b));        num=0;        for(i=n+1; i<=n*2; i++)        {            if(n*i%(i-n))continue;            p=n*i/(i-n);            a[num]=p;            b[num]=i;            num++;        }        printf("%d\n",num);        for(i=0; i<num; i++)            printf("1/%d = 1/%d + 1/%d\n",n,a[i],b[i]);    }}


原创粉丝点击