題目：
Friday the Thirteenth簡答：
/*
ID: lixianm1
PROG: friday
LANG: C++
*/
#include <fstream>
#include <iostream>
#include <vector>
#include <map>
#include <string>
#include <cassert>
inline bool IsLeapYear(unsigned int nYear) {return ((!(nYear&3))&&(0!=nYear%100))||(0==nYear%400);}
int main(int argc, char* argv[])
{
//////////////////////////////////////////////////////////////////////////open the file
std::string strInFile = "friday.in";
std::string strOutFile = "friday.out";
std::ifstream fin(strInFile.c_str());
std::ofstream fout(strOutFile.c_str());
if (!fin)
{
std::cout<<"failed to open file for read"<<std::endl;
return 1;
}
if (!fout)
{
std::cout<<"failed to open file for write"<<std::endl;
fin.close();
return 1;
}
//////////////////////////////////////////////////////////////////////////read file and init all variables
int N;
fin>>N;
//////////////////////////////////////////////////////////////////////////process
static int month_day[]={0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
static int month_day2[]={0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
int aWeekCount[7]={0};
unsigned int nTotalDays= 0;
for (int i=0; i<N; ++i)
{
for (int nMonth=1; nMonth<13; ++nMonth)
{
++aWeekCount[(nTotalDays+12)%7];
if (!IsLeapYear(1900+i))
{
nTotalDays+=month_day[nMonth];
}else
{
nTotalDays+=month_day2[nMonth];
}
}
}
//////////////////////////////////////////////////////////////////////////write the process result
for (int i=0; i<6; ++i)
{
fout<<aWeekCount[(i+5)%7]<<" ";
}
fout<<aWeekCount[4]<<std::endl;
//////////////////////////////////////////////////////////////////////////end and exit
fin.close();
fout.close();
//system("pause");
return 0;
}