Artifact 1da7b34c9052097a6cbddcd16e1a248867fd285d

• File SRM/341/1A.cpp
  • 2011-02-23 09:21:16 - part of checkin [4fd800b3a8] on branch trunk - Copied from private svn repository. (user: kinaba) [annotate]

#include <iostream>
#include <sstream>
#include <iomanip>
#include <vector>
#include <string>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <iterator>
#include <complex>
#include <queue>
#include <stack>
#include <cmath>
using namespace std;
typedef long long LL;

class KLastNonZeroDigits
{
public:
	string getKDigits(int N, int K) 
	{
		// 20! = 20*..*11*10! < 20*..*11*2^22
		//                    < 16^10 * 2^22
		//                    = 2^62

		// 10^K
		LL Z = 1;
		for(int i=0; i<K; ++i)
			Z *= 10;

		// N!
		LL x = 1;
		for(LL n=2; n<=N; ++n)
			x *= n;
		while(x%10==0)
			x /= 10;

		// Output
		stringstream sout;
		if( x < Z )
			sout << x;
		else
			sout << setw(K) << setfill('0') << x%Z;
		return sout.str();
	}

// BEGIN CUT HERE
	public:
	void run_test(int Case) { if ((Case == -1) || (Case == 0)) test_case_0(); if ((Case == -1) || (Case == 1)) test_case_1(); if ((Case == -1) || (Case == 2)) test_case_2(); if ((Case == -1) || (Case == 3)) test_case_3(); if ((Case == -1) || (Case == 4)) test_case_4(); if ((Case == -1) || (Case == 5)) test_case_5(); }
	private:
	template <typename T> string print_array(const vector<T> &V) { ostringstream os; os << "{ "; for (typename vector<T>::const_iterator iter = V.begin(); iter != V.end(); ++iter) os << '\"' << *iter << "\","; os << " }"; return os.str(); }
	void verify_case(int Case, const string &Expected, const string &Received) { cerr << "Test Case #" << Case << "..."; if (Expected == Received) cerr << "PASSED" << endl; else { cerr << "FAILED" << endl; cerr << "\tExpected: \"" << Expected << '\"' << endl; cerr << "\tReceived: \"" << Received << '\"' << endl; } }
	void test_case_0() { int Arg0 = 10; int Arg1 = 3; string Arg2 = "288"; verify_case(0, Arg2, getKDigits(Arg0, Arg1)); }
	void test_case_1() { int Arg0 = 6; int Arg1 = 1; string Arg2 = "2"; verify_case(1, Arg2, getKDigits(Arg0, Arg1)); }
	void test_case_2() { int Arg0 = 6; int Arg1 = 3; string Arg2 = "72"; verify_case(2, Arg2, getKDigits(Arg0, Arg1)); }
	void test_case_3() { int Arg0 = 7; int Arg1 = 2; string Arg2 = "04"; verify_case(3, Arg2, getKDigits(Arg0, Arg1)); }
	void test_case_4() { int Arg0 = 20; int Arg1 = 9; string Arg2 = "200817664"; verify_case(4, Arg2, getKDigits(Arg0, Arg1)); }
	void test_case_5() { int Arg0 = 1; int Arg1 = 1; string Arg2 = "1"; verify_case(5, Arg2, getKDigits(Arg0, Arg1)); }

// END CUT HERE
};
// BEGIN CUT HERE 
int main() { KLastNonZeroDigits().run_test(-1); }
// END CUT HERE