Cod sursa(job #2500921)
Utilizator | silviu ionut lutu | Data | 28 noiembrie 2019 20:51:38 |
---|---|---|---|
Problema | Fractii | Scor | 10 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva de probleme | Marime | 0.51 kb |
#include<iostream>
#include<fstream>
#include<cstring>
#include<math.h>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
char v[1000001];
int main()
{
int n,i,j,nr=0;
f>>n;
for(i=1;i<=n;i++)
{
for(j=2;j<=n;j++)
{
if(v[j]==0&&i/j==float(i)/j)
{
for(int k=j;k<=n;k=k+j)
v[k]=1;
}
}
for(j=1;j<=n;j++)
{
if(v[j]==0)
nr++;
else
v[j]=0;
}
}
g<<nr;
}