HDU 1056 HangOver 模拟 水题

题意：给你一个表达式：$f_n = \frac{1}{2}+ \frac{1}{3}+\ldots + \frac{1}{n+1}$ ，给你$f_n$的值，求。

思路：打表

坑点：需要加eps。

http://acm.hdu.edu.cn/showproblem.php?pid=1056

/*********************************************
    Problem : HDU 1056
    Author  : NMfloat
    InkTime (c) NM . All Rights Reserved .
********************************************/

#include <map>
#include <set>
#include <queue>
#include <cmath>
#include <ctime>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <iostream>
#include <algorithm>

#define rep(i,a,b)  for(int i = a ; i <= b ; i ++)
#define rrep(i,a,b) for(int i = b ; i >= a ; i --)
#define repE(p,u) for(Edge * p = G[u].first ; p ; p = p -> next)
#define cls(a,x)   memset(a,x,sizeof(a))
#define eps 1e-8

using namespace std;

const int MOD = 1e9+7;
const int INF = 0x3f3f3f3f;
const int MAXN = 1e5+5;
const int MAXE = 2e5+5;

typedef long long LL;
typedef unsigned long long ULL;

int T,m,k;
double n;

int sgn(double x) {
    if(fabs(x) < eps) return 0;
    return x > 0 ? 1 : - 1; 
}

double a[305];

void init() {
    rep(i,2,301) {
        a[i-1] = a[i-2] + 1.0 / i;
    }
}

void input() {

}

void solve() {
    rep(i,1,300) {
        if(sgn(a[i]-n)>=0) {
            printf("%d card(s)\n",i);
            break;
        }
    }
}

int main(void) {
    //freopen("a.in","r",stdin);
    //scanf("%d",&T); while(T--) {
    //while(~scanf("%d %d",&n,&m)) {
    init();
    while(scanf("%lf",&n),n) {
        input();
        solve();
    }
    return 0;
}