#include <stdio.h>
int halfsearch(int a[],int n,int x);
int main()
{
int a[10]={4,5,7,8,10,12,16,18,20,30},n,x;
scanf("%d",&x);
if(n=halfsearch(a,10,x)!=-1)
printf("%d %d",x,n);
else
;
return 0;
}
int halfsearch(int a[],int n,int x)
{
int s=0,e=n-1,m;
while(s<=e)
{
m=(s+e)/2;
if(a[m]==x)
return m;
else if(x>a[m])
s=m+1;
else
e=e-1;
}
return -1;
}
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