Light OJ 1234 Harmonic Number 调和级数部分和

题目来源：Light OJ 1234  Harmonic Number

题意：

思路：没思路啊 这个是高数的东西 发散 n足够大时它无穷大 直接公式解

#include <cstdio>
#include <cstring>
#include <cmath>
#include <string>
#include <algorithm>
#include <iostream>
using namespace std;
const int maxn = 1000010;
const double phi = 0.57721566490153286060651209;
double a[maxn];
int main()
{
	for(int i = 1; i <= 1000000; i++)
		a[i] = a[i-1] + 1.0/i;
    int cas = 1;
	int T;
	scanf("%d", &T);
	while(T--)
	{
		int n;
        scanf("%d", &n);
        double ans;
        if(n <= 1000000)
			ans = a[n];
        else
			ans = log(n+0.5) + phi;
        printf("Case %d: %.10lf\n", cas++, ans);
    }
    return 0;
}

Light OJ 1234 Harmonic Number 调和级数部分和