版权声明:写了自己看的,看不懂不能怪我emmmm。 https://blog.csdn.net/qq_40858062/article/details/83864724
题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=6217
思路:BBP模板题...
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <bitset>
#include <cmath>
#include <cctype>
#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <queue>
#include <map>
#include <set>
#include <sstream>
#include <iomanip>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
const ll inff = 0x3f3f3f3f3f3f3f3f;
#define FOR(i,a,b) for(int i(a);i<=(b);++i)
#define FOL(i,a,b) for(int i(a);i>=(b);--i)
#define REW(a,b) memset(a,b,sizeof(a))
#define inf int(0x3f3f3f3f)
#define si(a) scanf("%d",&a)
#define sl(a) scanf("%lld",&a)
#define sd(a) scanf("%lf",&a)
#define ss(a) scanf("%s",a)
#define mod ll(6666666)
#define pb push_back
#define eps 1e-6
#define lc d<<1
#define rc d<<1|1
#define Pll pair<ll,ll>
#define P pair<int,int>
#define pi acos(-1)
int n;
char as(int x)
{
if(x>=0&&x<=9) return x+'0';
else return x-10+'A';
}
ll gmod(ll a,ll b,ll c)
{
ll res=1;
while(b)
{
if(b&1) res=res*a%c;
b>>=1,a=a*a%c;
}
return res;
}
double BBP(int n,ll k,ll b)
{
double v=0;
FOR(i,0,n) v+=(gmod(16,n-i,8*i+b)*1.0/(8*i+b));
FOR(i,n + 1,n+1001) v+=(powf(16,n-i)/(8*i+b));
return k*v;
}
int main()
{
cin.tie(0);
cout.tie(0);
int t;
cin>>t;
FOR(j,1,t)
{
printf("Case #%d: ",j);
si(n);n--;
double v=BBP(n,4,1)-BBP(n,2,4)-BBP(n,1,5)-BBP(n,1,6);
v=v-(int)v;
if(v<0) v+=1.0;
v*=16.0;
//cout<<v<<endl;
printf("%d %c\n",n+1,as((int)v));
}
return 0;
}