HDU - 6288 缺失的数据范围 (裸二分)

题意: 给你一个a,b,k问你n^a*(logn)^b中n的最大值

思路: 裸二分枚举n就好了,比较坑的是,好像要开一下unsigned long long

代码:

#include <bits/stdc++.h>
using namespace std;
int a,b;
#define ll long long
using it = __int128;
unsigned long long k;
int L(ll n)
{
	return ceil(log2(n));
}
int check(it x)
{
	it ans = 1;
	for(int i = 0 ; i < a ; i++)
	{
		ans = ans * x;
		if(ans > k )return 0;
	}
	it te = L(x);
	for(int i = 0 ; i < b ; i++)
	{
		ans *= te;
		if(ans > k) return 0;
	}
	return 1;
}
int main()
{
	int t;
	scanf("%d",&t);
	while(t--)
	{
		scanf("%d%d%llu",&a,&b,&k);
		ll  l = 0 , r = 1e18;
		ll ans = 0;
		while(l<r)
		{
			unsigned long long m = l+(r-l)/2;
			if(check(m))
			{
				l = m+1;
				ans = m;
			 }
			else r = m;
		}
		printf("%lld\n",ans);
	}
}

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转载自blog.csdn.net/wjmwsgj/article/details/80519865