SRM 400 DIV2 [500]

#include<iostream>
#include<string>
#include<vector>
#include<set>
#include<algorithm>
#include<memory.h>
#include<cmath>
#include<cstdio>
using namespace std;

long long num;

bool is(int p,int q)
...{
    long long temp=1;
    for (int i=0;i!=q;++i)
        temp*=(long long)p;
    if (temp!=num) return false;
    for (int i=2;i*i<=p;++i)
        if (p%i==0) return false;
    return true;
}

class StrongPrimePower...{
public:
    vector <int> baseAndExponent(string n)
    ...{
        vector<int> ans;
        sscanf(n.c_str(),"%lld",&num);
        double f=num;
        for (int i=2;i!=65;++i)...{
            int p=pow(f,(double)1/i)+0.5;
            if (is(p,i))...{
                ans.push_back(p);
                ans.push_back(i);
                return ans;
            }
        }
        return ans;
    }
};

Problem Statement

    

NOTE: This problem statement contains superscripts that may not display properly if viewed outside of the applet.

A number which can be represented as p^q, where p is a prime number and q is an integer greater than 0, is called a prime power. If q is larger than 1, we call the number a strong prime power. You are given an integer n. If n is a strong prime power, return an vector <int> containing exactly two elements. The first element is p and the second element is q. If n is not a strong prime power, return an empty vector <int>.

Definition

     Class: StrongPrimePower Method: baseAndExponent Parameters: string Returns: vector <int> Method signature: vector <int> baseAndExponent(string n) (be sure your method is public)       

Constraints

- n will contain digits ('0' - '9') only. - n will represent an integer between 2 and 10^18, inclusive. - n will have no leading zeros.

Examples

0)       

"27"

Returns: {3, 3 }

27 = 3³. This is a strong prime power. 1)       

"10"

Returns: { }

10 = 2 * 5. This is not a strong prime power. 2)       

"7"

Returns: { }

A prime number is not a strong prime power. 3)       

"1296"

Returns: { }

  4)       

"576460752303423488"

Returns: {2, 59 }

  5)       

"999999874000003969"

Returns: {999999937, 2 }

 

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