zoukankan      html  css  js  c++  java

# Co-prime

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 2789    Accepted Submission(s): 1074

Problem Description
Given a number N, you are asked to count the number of integers between A and B inclusive which are relatively prime to N. Two integers are said to be co-prime or relatively prime if they have no common positive divisors other than 1 or, equivalently, if their greatest common divisor is 1. The number 1 is relatively prime to every integer.

Input
The first line on input contains T (0 < T <= 100) the number of test cases, each of the next T lines contains three integers A, B, N where (1 <= A <= B <= 1015) and (1 <=N <= 109).

Output
For each test case, print the number of integers between A and B inclusive which are relatively prime to N. Follow the output format below.

Sample Input
2 1 10 2 3 15 5

Sample Output
Case #1: 5 Case #2: 10
Hint
In the first test case, the five integers in range [1,10] which are relatively prime to 2 are {1,3,5,7,9}.

1.容斥初涉
2.找到交叉情况，即有条理的分析题目  ```#include<iostream>
#include<cstdio>
#include<string.h>
__int64 a,num;
void gett(__int64 n)
{
__int64 i;
num=0;
for(i=2;i*i<=n;i++)
{
if(n%i==0)
{
a[num++]=i;
while(n%i==0)
n=n/i;
}
}
if (n>1)
a[num++]=n;
}
__int64 rc(__int64 m)
{
__int64 q,i,j,k,t=0,sum=0;
q[t++]=-1;
for(i=0;i<num;i++)
{
k=t;
for(j=0;j<k;j++)
q[t++]=q[j]*a[i]*(-1);
}
for(i=1;i<t;i++)
sum=sum+m/q[i];
return sum;
}
int main()
{
__int64 T,x,y,n,sum;
while (scanf("%I64d",&T)!=EOF)
{
for (int j=1;j<=T;j++)
{
scanf("%I64d %I64d %I64d",&x,&y,&n);
gett(n);
sum=y-rc(y)-(x-1-rc(x-1));
printf("Case #%d: ",j);
printf("%I64d
",sum);
}
}
}```
View Code

• 相关阅读:
jstl标签
get和post
try中的局部变量在finally中是找不到的。
bzoj 4408: [Fjoi 2016]神秘数 数学 可持久化线段树 主席树
ZOJ2112 BZOJ1901 Dynamic Rankings 树套树 带修改的区间第k小
BZOJ 2120: 数颜色 带修改的莫队算法 树状数组套主席树
POJ2104 K-th Number 不带修改的主席树 线段树
POJ 2891 Strange Way to Express Integers 中国剩余定理 数论 exgcd
POJ1151 Atlantis 水题 计算几何
BZOJ 2333: [SCOI2011]棘手的操作 可并堆 左偏树 set
• 原文地址：https://www.cnblogs.com/xfjy/p/4991317.html