答案:8879
#include<iostream>
using namespace std;
int ans;
bool isleap(int y)
{
return (y % 4 == 0 && y % 100 != 0) || y % 400 ==0;
}
int main()
{
for(int y = 2000,m = 1, d = 1,w = 6; ; d++,w++)
{
if(d == 32 && m == 12)
{
y++;
m = 1;
d = 1;
}
if(d == 32 && (m == 1 || m == 3 || m == 5 || m == 7 || m == 8 || m == 10))
{
m++;
d = 1;
}
if(d == 31 && (m == 4 || m == 6 || m == 9 || m == 11))
{
m++;
d = 1;
}
if(d == 30 && m == 2 && isleap(y))
{
m++;
d = 1;
}
if(d == 29 && m == 2 && !isleap(y))
{
m++;
d = 1;
}
if(w % 7 == 1 || d == 1) ans++;
ans++;
//cout << ans << endl;
if(y == 2020 && m == 10 && d == 1) break;
}
cout << ans << endl;
return 0;
}