Cod sursa(job #169868)
Utilizator | Gagos Radu Vasile Gagos | Data | 2 aprilie 2008 08:38:30 |
---|---|---|---|
Problema | Dezastru | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.43 kb |
#include<stdio.h>
int st[26],n,k,nr;
float v[26],p=1;
void bkt(int l)
{
int i;
if(l==k){
nr++;
float r=1;
for(i=1;i<=k;i++)
r*=v[st[i]];
p+=r;
}
else
for(i=st[l]+1;i<=n;i++){
st[l+1]=i;
bkt(l+1);
}
}
int main()
{
int i;
freeopen("dezastru.in","r",stdin);
freeopen("dezastru.out","w",stdout);
scanf("%d%d",&n,&k);
for(i=1;i<=n;i++)
scanf("%f",&v[i]);
printf("%.6f",p/nr);
return 0;
}