【HDU 6182】A Math Problem
A Math Problem
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 4965 Accepted Submission(s): 1543
Problem Description
You are given a positive integer n, please count how many positive integers k satisfy kk≤n.
Input
There are no more than 50 test cases.
Each case only contains a positivse integer n in a line.
1≤n≤10^18
Output
For each test case, output an integer indicates the number of positive integers k satisfy kk≤n in a line.
Sample Inpu
1 4
Sample Output
1 2
大海啊全是水,骏马啊四条腿~
根据数据范围,只需要求出前15个k^k即可。
代码:
#include<iostream>
#include<algorithm>
#include<cstring>
#include<string>
#include<cstdio>
#include<cmath>
#include<set>
#include<map>
using namespace std;
#define ll long long
#define inf 0x3f3f3f3f
#define mem(a,b) memset(a,b,sizeof(a))
#define closeio std::ios::sync_with_stdio(false)
ll a[20];
int main()
{
int i,j;
ll n;
for(i=1;i<=15;i++)
{
a[i]=1;
for(j=1;j<=i;j++)
a[i]*=i;
}
while(cin>>n)
{
int s=0;
for(i=1;i<=15;i++)
{
if(a[i]<=n)
s++;
else
break;
}
cout<<s<<endl;
}
return 0;
}