URAL1049[Brave balloonists]

水题，将十个数的乘积分解成a1^n1*a2^n2*…*ak^nk的形式（当然不要先乘再分解）。然后结果为(n1+1)*(n2+1)*…*(nk+1) mod 10。

CODE:

/*

PROGRAM: $PROGRAM

AUTHOR: Su Jiao

DATE: 2010-3-26

DESCRIPTION:

$DESCRIPTION

*/

#include <iostream>

using std::cin;

using std::cout;

#include <fstream>

using std::ifstream;

using std::ofstream;

#include <sstream>

using std::stringstream;

using std::endl;

#include <vector>

using std::vector;

#include <string>

using std::string;

#include <stack>

using std::stack;

#include <queue>

using std::queue;

#include <set>

using std::set;

#include <map>

using std::map;

using std::pair;

using std::make_pair;

#include <algorithm>

using std::sort;

#include <cassert>

//using std::assert;

 

class Application

{

      static const int NUMBER=10;

      static const int oo=10000;

      vector<int> a;

      int last_digit_of_N;

      vector<int> counter;

      public:

      Application()

                   :a(NUMBER)

      {

                   for (int i=0;i<NUMBER;i++) cin>>a[i];

      }

      int run()

      {

          counter.resize(oo+1,1);

          for (int i=0;i<NUMBER;i++)

              for (int j=2;j<=oo;j++)

                  while (a[i]%j==0) counter[j]++,a[i]/=j;

          last_digit_of_N=1;

          for (int i=0;i<=oo;i++)

              last_digit_of_N=last_digit_of_N*counter[i]%10;

          cout<<last_digit_of_N<<endl;

          return 0;

      }

};

 

int main()

{

    Application app;

    return app.run();

}