Pagini recente » Cod sursa (job #708019) | Cod sursa (job #1391123) | Cod sursa (job #1373404) | Cod sursa (job #2454040) | Cod sursa (job #635051)
Cod sursa(job #635051)
#include <fstream>
#include <algorithm>
using namespace std;
#define unusable -100000
int n, m;
int d[1000001];
long long sol;
int main ()
{
int i, j, minim = 0;
freopen ("mins.in", "r", stdin);
freopen ("mins.out", "w", stdout);
scanf ("%d %d", &n, &m);
n--;m--;
minim = min(n, m);
for(i = 2; i <= minim; ++i)
if(d[i] == 0)
{
for(j = i * i; j <= minim; j += i * i)
d[j] = unusable;
for(j = i; j <= minim; j += i)
++d[j];
}
for (i = 2; i <= minim; i ++)
if (d[i] > 0)
{
if (d[i] & 1)
sol -= (long long)(n / i) * (m / i);
else
sol += (long long)(n / i) * (m / i);
}
printf("%lld", sol + (long long)n * m);
return 0;
}